Doped asymmetric two-band Hubbard models Peter van Dongen 25 August 2009

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Doped asymmetric two-band Hubbard models

Doped asymmetric two-band Hubbard models

Peter van Dongen

25 August 2009

EPSRC Symposium Workshop on Quantum Simulations

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Overview

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Part 1: Results at half-filling ( n = 2)

The spectral function

Magnetic phase diagram

Part 2: results away from half-filling ( n = 2)

Static properties

Phase diagram

Dynamical properties

Part 3: n = 2 , including crystal field splitting

static properties

Phase diagram and spectral functions

Summary

Appendix

Perturbation theory results

Introduction to DMFT

Additional results at and away from half-filling

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Orbital-selective Mott transitions in Ca

2 − x

Sr x

RuO

4

Experimental phase diagram of Ca

2 − x

Sr x

RuO

4

:

[S. Nakatsuji, Y. Maeno,

PRL 84 , 2666 (2000)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Orbital-selective Mott transitions in Ca

2 − x

Sr x

RuO

4

Experimental phase diagram of Ca

2 − x

Sr x

RuO

4

:

[S. Nakatsuji, Y. Maeno,

PRL 84 , 2666 (2000)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Orbital-selective Mott transitions in Ca

2 − x

Sr x

RuO

4

Experimental phase diagram of Ca

2 − x

Sr x

RuO

4

:

[S. Nakatsuji, Y. Maeno,

PRL 84 , 2666 (2000)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ 0

Rotational invariance:

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0 X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

J

3

= J

= J

0 ≡ J i m

U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian?

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ 0

Rotational invariance:

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0 X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

J

3

= J

= J

0 ≡ J i m

U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0

X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ i m

Rotational invariance: J

3

= J

= J

0 ≡ J U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0

X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

Rotational invariance: J

3

= J

= J

0

≡ J i m

U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0

X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

Rotational invariance: J

3

= J

= J

0

≡ J i m

U

0

= U − 2 J

In QMC -calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0

X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

Rotational invariance: J

3

= J

= J

0

≡ J i m

U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Introduction: experimental motivation and Hamiltonian

Phase diagram of Ca

2 − x

Sr x

RuO

4

, two-band Hubbard model

Two-band Hubbard model for Ca

2 − x

Sr x

RuO

4

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

+ U

X n i m ↑ n i m ↓

( ij ) m σ i m

+

X

( U

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0 i σσ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0

X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ

Rotational invariance: J

3

= J

= J

0

≡ J i m

U

0

= U − 2 J

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Expansion of self-energy for multi-band Hubbard models:

Σ

γ

( ω ) =

X

U

αγ h n

α i +

α = γ

1

X X

U

αγ

U

βγ

ω

α = γ β = γ

( h n

α n

β i − h n

α ih n

β i ) + O ( ω

− 2

)

[Also by V.S. Oudovenko and G. Kotliar, PRB 65 , 75102 (2002)]

[See also J.K. Freericks and V. Turkowski, PRB (to be published)]

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

The spectral function

Part 1: n = 2 , spectral functions

(narrow/wide band)

0.2

0.1

0.0

0.1

0.2

0.3

0.6

0.5

0.4

0.3

0

T=1/40, "# =0.40

narrow band

U=0.0

U=1.8

U=2.05

U=2.2

U=2.4

U=2.6

U=2.8

1 wide band (inverted scale)

2

!

3 4

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

The spectral function

Part 1: n = 2 , spectral functions

(narrow/wide band)

0.2

0.1

0.0

0.1

0.2

0.3

0.6

0.5

0.4

0.3

0

T=1/40, "# =0.40

narrow band

U=0.0

U=1.8

U=2.05

U=2.2

U=2.4

U=2.6

U=2.8

1 wide band (inverted scale)

2

!

3 4

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

The spectral function

Spectral weight at Fermi level

(narrow/wide band) narrow band

T=1/40

T=1/32

T=1/25

0.6

0.5

0.4

0.3

0.2

0.1

0

1.8

2 wide band

2.2

U

2.4

2.6

2.8

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

The spectral function

Self energy at low frequencies

(narrow/wide band) a)

2

1 b)

0

2

2

1

0

T=1/32 narrow band

U=2.8

U=2.6

U=2.4

U=2.2

U=2.0

U=1.8

2

U

2.5

3 wide band

1

0

0 0.2

0.4

0.6

!

0.8

1 1.2

n = 2

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

The spectral function

Self energy at low frequencies

(narrow/wide band) a)

2

1 b)

0

2

2

1

0

T=1/32 narrow band

U=2.8

U=2.6

U=2.4

U=2.2

U=2.0

U=1.8

2

U

2.5

3 wide band

1

0

0 0.2

0.4

0.6

!

0.8

1 1.2

n = 2

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

Magnetic phase diagram

Results at half-filling: magnetic phase diagram

0.25

0.2

1 band

2 bands

Strong-coupling limit (1OPT)

Weak-coupling limit (2OPT)

0.15

PM

0.1

MIT of 1-band HM

AF

MIT of narrow band

0.05

0

0 1 2 3

U

4 5 6 7 appendix

Doped asymmetric two-band Hubbard models

Part 1: Results at half-filling ( n = 2)

Magnetic phase diagram

Results at half-filling: magnetic phase diagram

0.25

0.2

1 band

2 bands

Strong-coupling limit (1OPT)

Weak-coupling limit (2OPT)

0.15

PM

0.1

MIT of 1-band HM

AF

MIT of narrow band

0.05

0

0 1 2 3

U

4 5 6 7

appendix

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Static properties

Part 2: n = 2 , U -dependence of orbital occupancy

1.3

U=2.80

U=2.60

U=2.40

U=2.20

U=2.00

U=1.80

1.2

wide band

1.1

narrow band

1

2 2.1

2.2

2.3

n (total filling)

2.4

2.5

2.6

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Static properties

Part 2: n = 2 , U -dependence of orbital occupancy

1.3

U=2.80

U=2.60

U=2.40

U=2.20

U=2.00

U=1.80

1.2

wide band

1.1

narrow band

1

2 2.1

2.2

2.3

n (total filling)

2.4

2.5

2.6

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Static properties

Rigid-band model ↔ QMC results a) wide band narrow band b)

1.3

wide band (RB) narrow band (RB) wide band (QMC) narrow band (QMC)

1.2

1.1

-4 -3 -2 -1 0 1 2 3 4

!

1.0

2 2.1

2.2

n (total filling)

2.3

Phase diagram

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Static properties

Rigid-band model ↔ QMC results a) wide band narrow band b)

1.3

wide band (RB) narrow band (RB) wide band (QMC) narrow band (QMC)

1.2

1.1

-4 -3 -2 -1 0 1 2 3 4

!

1.0

2 2.1

2.2

n (total filling)

2.3

Phase diagram

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Static properties

U -dependence of intraorbital double occupancy b)

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0

2

U=2.80

U=2.40

U=2.00

U=2.40 (HF)

U=0.00

2.5

narrow band

3 n (total filling) wide band

3.5

4

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Phase diagram

Phase diagram of the doped two-band Hubbard model fully metallic phase orbital-selective Mott phase

U c1

at half-filling

U c2

at half-filling

Mott insulating phase (black line)

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Phase diagram

Phase diagram of the doped two-band Hubbard model

Narrow band provides major contribution

Wide band provides major contribution

2

1.6

U c1

at half-filling orbital-selective Mott phase

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

DOS at Fermi-level

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0

2 2.1

narrow band wide band

2.2

2.3

n (total filling)

2.4

U=2.80

U=2.60

U=2.40

U=2.20

U=2.00

2.5

2.6

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

Imaginary part of the self-energy a) 0.0

b)

T=1/40

-0.2

n=2.20

-0.4

-0.6

-0.8

-1.0

0 n=2.10

1 n=2.25

n=2.20

n=2.15

n=2.10

n=2.05

2

" n

3 4 0 1

T=1/20

T=1/30

T=1/40

2

" n

3 4

Part 3

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

Imaginary part of the self-energy a) 0.0

b)

T=1/40

-0.2

n=2.20

-0.4

-0.6

-0.8

-1.0

0 n=2.10

1 n=2.25

n=2.20

n=2.15

n=2.10

n=2.05

2

" n

3 4 0 1

T=1/20

T=1/30

T=1/40

2

" n

3 4

Part 3

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

DOS for wide band ↔ DOS for single-band model:

˜

= 0 .

855

Two-band model narrow band

Single-band model n = 2.20

n = 1.09

-3 -2 -1 0

E

1 n = 2.00

2 3 -3 -2 -1 0

E

1 n = 1.00

2 3

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

DOS for wide band ↔ DOS for single-band model:

˜

= 0 .

945

Two-band model narrow band

Single-band model n = 2.20

n = 1.08

-3 -2 -1 0

E

1 n = 2.00

2 3 -3 -2 -1 0

E

1 n = 1.00

2 3

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

DOS for wide band ↔ DOS for single-band model:

˜

= 1 .

035

Two-band model narrow band

Single-band model n = 2.20

n = 1.06

-3 -2 -1 0

E

1 n = 2.00

2 3 -3 -2 -1 0

E

1 n = 1.00

2 3

Doped asymmetric two-band Hubbard models

Part 2: results away from half-filling ( n = 2)

Dynamical properties

DOS for wide band ↔ DOS for single-band model:

˜

= 1 .

125

Two-band model narrow band

Single-band model n = 2.20

n = 1.05

-3 -2 -1 0

E

1 n = 2.00

2 3 -3 -2 -1 0

E

1 n = 1.00

2 3

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Part 3: n = 2 , including crystal field splitting

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

( ij ) m σ

+ U

X n i m ↑ n i m ↓

+

X

( U

0 i m i σσ

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0 X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓

+

1

2

X

( n i 1

− n i 2

) i σ i m i

In QMC-calculations: J

= J

0

= 0 U

0

=

1

2

U J

3

=

1

4

U

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Part 3: n = 2 , including crystal field splitting

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

( ij ) m σ

+ U

X n i m ↑ n i m ↓

+

X

( U

0 i m i σσ

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0 X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ i m

+

1

2

X

( n i 1 i

− n i 2

)

In QMC-calculations: J

= J

0

= 0 U

0

=

1

2

U J

3

=

1

4

U

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Part 3: n = 2 , including crystal field splitting

Hamiltonian:

H = −

X t m c

† i m σ c j m σ

( ij ) m σ

+ U

X n i m ↑ n i m ↓

+

X

( U

0 i m i σσ

0

− J

3

δ

σσ

0

) n i 1 σ n i 2 σ

0

− J

X c

† i 1 σ c i 1 ¯ c

† i 2 ¯ c i 2 σ

− J

0 X c

† i m ↑ c

† i m ↓ c i ¯ ↑ c i ¯ ↓ i σ i m

+

1

2

X

( n i 1 i

− n i 2

)

In QMC-calculations: J

= J

0

= 0 U

0

= 1

2

U J

3

= 1

4

U

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting static properties

Orbital-dependent filling

2 n=n w

+n n

=2.00

Wide Band

1.5

2 n=n w

+n n

=2.20

1.5

1 1

0.5

Narrow Band

0

-4 -3 -2 -1 0 1 2 3 4

Crystal field splitting

0.5

0

U = 4.00

U = 3.60

U = 3.20

U = 2.80

U = 2.40

U = 2.00

-4 -3 -2 -1 0 1 2 3 4

Crystal field splitting

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting static properties

Intraorbital double occupancy

1

Wide Band

0.8

Narrow Band

0.6

1

0.8

0.6

U = 4.00

U = 3.60

U = 3.20

U = 2.80

U = 2.40

U = 2.00

0.4

0.4

0.2

0 n=n w

+n n

=2.10

-4 -3 -2 -1 0 1 2 3 4

Crystal field splitting

0.2

n=n w

+n n

=2.20

0

-4 -3 -2 -1 0 1 2 3 4

Crystal field splitting

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Phase diagram and spectral functions

The phase diagram

5

4.5

Band insulator narrow band n=2.10

4

3.5

3

2.5

2

1.5

-4

OSMP wide band n=2.10

increase filling

OSMP narrow band n=2.10

Band insulator

-3

U c

for wide B, n=2.10

U c

for narrow B, n=2.10

U c

for wide B, n=2.20

U c

for narrow B, n=2.20

-2 -1 0

Crystal field splitting

1

Metallic regime

Non-Fermi liquid

2 3 wide band n=2.10

increase filling

4

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Phase diagram and spectral functions

DOS at selected points in the phase diagram

5

4.5

Band insulator narrow band n=2.10

4

3.5

3

2.5

2

1.5

-4

OSMP wide band n=2.10

U=3.00,

=-2.20

Wide band

Narrow band

-3

U c

for wide B, n=2.10

U c

for narrow B, n=2.10

U c

for wide B, n=2.20

U c

for narrow B, n=2.20

-2 -1 0

Crystal field splitting

1

-6 -4 -2 0 2 4 6

E

2 3 4

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Phase diagram and spectral functions

DOS at selected points in the phase diagram

5

4.5

Band insulator narrow band n=2.10

4

3.5

3

2.5

2

1.5

-4

OSMP wide band n=2.10

U=4.00,

Wide band

Narrow band

=-1.60

-3

U c

for wide B, n=2.10

U c

for narrow B, n=2.10

U c

for wide B, n=2.20

U c

for narrow B, n=2.20

-2 -1 0

Crystal field splitting

1

-6 -4 -2 0 2 4 6

E

2 3 4

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Phase diagram and spectral functions

DOS at selected points in the phase diagram

5

4.5

4

3.5

3

2.5

2

1.5

-4

U=3.00,

=2.60

Wide band

Narrow band

OSMP narrow band n=2.10

Band insulator wide band n=2.10

U c

for wide B, n=2.10

U c

for narrow B, n=2.10

-6 -4 U c

for wide B, n=2.20

U c

-3 -2 -1 0

Crystal field splitting

1

Metallic regime

Non-Fermi liquid

2 3 4

Doped asymmetric two-band Hubbard models

Part 3: n = 2, including crystal field splitting

Phase diagram and spectral functions

DOS at selected points in the phase diagram

5

4.5

4

3.5

3

2.5

2

1.5

-4

U=3.40,

=0.60

Wide band

Narrow band

OSMP narrow band n=2.10

Band insulator wide band n=2.10

U c

for wide B, n=2.10

U c

for narrow B, n=2.10

-6 -4 U c

for wide B, n=2.20

U c

-3 -2 -1 0

Crystal field splitting

1

Metallic regime

Non-Fermi liquid

2 3 4

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models

:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling

I

I

I

:

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping

I

I

I

:

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting

I

I

:

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Summary

Summary

Doped asymmetric two-band Hubbard models:

1.

at half-filling:

I

I

I

. . .

as a model for OSMTs (Ca

2 − x

Sr x

RuO

4

)

Results: orbital selective Mott phase , non-Fermi-liquid magnetic phase diagram: weak coupling AFM

2.

for general doping:

I

I

I

OSMTs even away from half-filling n ' 2: pinning of particle density of narrow band

Phase diagram and DOS as a function of interaction/filling

3.

including crystal field splitting:

I

I

OSMTs also in presence of crystal field splitting

Phase diagram and DOS including crystal field splitting

Thanks for your attention!

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling

I Effective Hamiltonians for J

< J

3

H t

0 and J

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

= J

3

≡ J :

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

:

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling

I Effective Hamiltonians for J

< J

3

H t

0 and J

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

= J

3

≡ J :

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

:

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling

I Effective Hamiltonians for J

< J

3

H t

0 and J

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

= J

3

≡ J :

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

:

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling

I Effective Hamiltonians for J

< J

3

H t

0 and J

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

= J

3

≡ J :

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

:

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

Perturbation theory at strong coupling

T c

∼ T

HF c exp − t

1 b

2

ν (0)

I

:

Effective Hamiltonians for J

< J

3

H t

0 and J

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

= J

3

≡ J :

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling:

I Effective Hamiltonians for J

< J

3

H t

0 and J

= J

3

≡ J :

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

Perturbation theory at weak and strong coupling

Self-consistent perturbation theory at weak coupling:

I Expand free energy: f ( U , ∆) = f

0

(∆) + Uf

1

(∆) + U

2 f

2

(∆) + · · ·

I

I

Keep order parameter fixed: h ( U , ∆) = h

0

(∆) + Uh

1

(∆) + U

2 h

2

(∆) + · · ·

Optimize in each order: df d ∆

= 0 k

B

T

HF c

∼ t

1

∗ exp I d

− t

1

∗ b

1

U ν (0)

T c

∼ T

HF c exp − t

1 b

2

ν (0)

Perturbation theory at strong coupling:

I Effective Hamiltonians for J

< J

3

H t

0 and J

= J

3

≡ J :

=

X

J

Heis

( S i

· S j

− n i n j

) ↔ H t

0

=

X

J

Is

( S i 3

( T = 0)

· S j 3

− n i n j

) h ij i h ij i

I Critical temperature: k

B

T c

( t

1

)

2

+ (

U + J t

2

)

2

(2nd order)

= ZJ

Heis

↔ k

B

T c

( t

1

)

2

+ ( t

2

)

2

U + J

3

= ZJ

Is

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

DOS of two-band Hubbard model at strong coupling

Sketch of density of states (non-interacting):

ν m σ

( ω ) phase diagram m = 1

ω m = 2

0

Density of states for

ν

LHB m σ

ν

LHB m σ

( ω ) =

( ω ) =

2

3

J

ν

0 m

(

<

»

J

4

3

3 and

ν

0 m

(

2 [ ω +

[ ω +

1

2

1

2

J

= J

3

( U + J

3

)])

( U + J )])

≡ J : ( T = 0)

( J

< J

3

)

( J

= J

3

)

ω

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

DOS of two-band Hubbard model at strong coupling

Sketch of density of states ( non-interacting ):

ν m σ

( ω ) m = 1

ω m = 2

0

ω phase diagram

Density of states for

ν

LHB m σ

ν

LHB m σ

( ω ) =

( ω ) =

2

3

J

ν

0 m

(

<

»

J

4

3

3 and

ν

0 m

(

2 [ ω +

[ ω +

1

2

1

2

J

= J

3

( U + J

3

)])

( U + J )])

≡ J : ( T = 0)

( J

< J

3

)

( J

= J

3

)

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

DOS of two-band Hubbard model at strong coupling

Sketch of density of states ( at strong coupling ):

ν m σ

( ω ) m = 1

ω m = 2

0

ω phase diagram

Density of states for

ν

LHB m σ

ν

LHB m σ

( ω ) =

( ω ) =

2

3

J

ν

0 m

(

<

»

J

4

3

3 and

ν

0 m

(

2 [ ω +

[ ω +

1

2

1

2

J

= J

3

( U + J

3

)])

( U + J )])

≡ J : ( T = 0)

( J

< J

3

)

( J

= J

3

)

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

DOS of two-band Hubbard model at strong coupling

Sketch of density of states (at strong coupling):

ν m σ

( ω ) m = 1

ω m = 2

0

Density of states for

ν

LHB m σ

ν

LHB m σ

( ω ) =

( ω ) =

2

3

J

ν

0 m

(

<

»

J

4

3

3 and

ν

0 m

(

2 [ ω +

[ ω +

1

2

1

2

J

= J

3

( U + J

3

)])

( U + J )])

≡ J : ( T = 0)

( J

< J

3

)

( J

= J

3

)

ω phase diagram

Doped asymmetric two-band Hubbard models

Appendix

Perturbation theory results

DOS of two-band Hubbard model at strong coupling

Sketch of density of states (at strong coupling):

phase diagram

ν m σ

( ω ) m = 1

ω m = 2

0

Density of states for

ν

LHB m σ

ν

LHB m σ

( ω ) =

( ω ) =

2

3

J

ν

0 m

(

<

»

J

4

3

3 and

ν

0 m

(

2 [ ω +

[ ω +

1

2

1

2

J

= J

3

( U + J

3

)])

( U + J )])

≡ J : ( T = 0)

( J

< J

3

)

( J

= J

3

)

ω

Doped asymmetric two-band Hubbard models

Appendix

Introduction to DMFT

Dynamical Mean Field Theory (DMFT)

DMFT maps lattice problem onto SIAM

⇔ neglects non-local correlations

⇔ assumes local self-energy Σ( k , ω )

!

= Σ( ω )

Several impurity solvers for SIAM available (QMC, NCA, NRG, ED, IPT, · · · )

Doped asymmetric two-band Hubbard models

Appendix

Introduction to DMFT

Dynamical Mean Field Theory (DMFT)

DMFT maps lattice problem onto SIAM

⇔ neglects non-local correlations

⇔ assumes local self-energy Σ( k , ω )

!

= Σ( ω )

Several impurity solvers for SIAM available (QMC, NCA, NRG, ED, IPT, · · · )

Doped asymmetric two-band Hubbard models

Appendix

Introduction to DMFT

Dynamical Mean Field Theory (DMFT)

DMFT maps lattice problem onto SIAM

⇔ neglects non-local correlations

⇔ assumes local self-energy Σ( k , ω )

!

= Σ( ω )

Several impurity solvers for SIAM available (QMC, NCA, NRG, ED, IPT, · · · )

Doped asymmetric two-band Hubbard models

Appendix

Introduction to DMFT

Dynamical Mean Field Theory (DMFT)

DMFT maps lattice problem onto SIAM

⇔ neglects non-local correlations

⇔ assumes local self-energy Σ( k , ω )

!

= Σ( ω )

Several impurity solvers for SIAM available (QMC, NCA, NRG, ED, IPT, · · · )

Doped asymmetric two-band Hubbard models

Appendix

Introduction to DMFT

Numerical implementation of DMFT

DMFT iteration scheme:

Doped asymmetric two-band Hubbard models

Appendix

Additional results at and away from half-filling

Result:

ratio of QP-renormalization factors:

r

Z narrow

/ Z wide

-0.7

a)

-0.8

T=1/25

T=1/32

T=1/40

0.7

0.6

0.5

b)

0.4

0.3

0.2

0.1

0

1.8

I

2

0.4

0.2

0

2

II

U

2.5

2.2

U

2.4

2.6

III

2.8

Doped asymmetric two-band Hubbard models

Appendix

Additional results at and away from half-filling

Result: intra-orbital double occupancies

( m =narrow,wide)

0.38

a) wide band

0.37

b) T=1/25

T=1/40

0.15

0.1

wide band

0.05

narrow band

0

1.8

2 2.2

U

2.4

2.6

2.8

Doped asymmetric two-band Hubbard models

Appendix

Additional results at and away from half-filling

Quasi-particle weight for narrow band a) 0.4

0.3

0.2

0.6

0.5

0.4

0.3

0.2

0.1

0.0

2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7

U=3.00

U=2.80

U=2.60

U=2.40

U=2.20

U=2.00

0.1

0

2 2.1

n (total filling)

2.2

2.3

Doped asymmetric two-band Hubbard models

Appendix

Additional results at and away from half-filling

Real part of the self-energy b)

3

2.5

2

1.5

wide band n=2.60

n=2.40

n=2.20

n=2.15

n=2.10

n=2.05

n=2.00

1

0.5

0

0 0.5

1 1.5

2 2.5

" n narrow band

0 0.5 1 1.5 2 2.5

" n

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