Ana Maria Rey, Deborah Jin and Jun Ye JILA, NIST and University of Colorado DARPA OLE Review, Polar Molecules Miami, Nov 27, 2012 Optical atomic clocks Coherent spectroscopy Nicholson et al., arXiv:1210.0064 3P (e) 0 3P 0- 1S 1S (g) 0 0: Effective spin 1/2 system during clock interrogation With atom-light coherence times reaching several seconds, even very weak interactions can dominate the dynamics. Collective-spin S reactive Vab: p-wave int Uab: s-wave int S x ,y ,z Snx , y , z n n: Harmonic oscillator mode Ramsey fringe decay vs. the spin tipping angle Mean field. N- dependent effective B field H 2 Sz CN S z Quantum fluctuactions Further decay Poissonian distribution Ramsey fringe dephasing Full master Eq. Normalized Contrast Normalized Contrast 1D (nˆ S ) 2 2 4 Laser 2 N 2 one-axis twisting 900 atoms 20 ms 4000 atoms KitagawaLaser+Many-body & Ueda, PRA, 1993. 20 ms (spin squeezing) Polzik, Vuletic, Thompson … Laser 40 ms 40 ms () () Reactive collisions: M. Foss-Feig et al, arXiv:1207.4741, PRL (in press) Conventional wisdom: losses are a problem to be avoided. Are there any circumstances under which they can be exploited? Under certain reasonable conditions, yes! - Two component fermions - Non degenerate (allowing for incoherent spin mixtures) - Still ultracold, so that s-wave scattering dominates Losses induce entanglement, no engineering!! SU(N) Heisenberg Models N=2I+1 I: nuclear spin N=10 in Sr Quantum Magnetism and beyond: Chiral Spin Liquids, Valence Bond solids,.. Hermele, Gurarie, AMR PRL 103, 135301 (2009) Adiabatic Loading Optical lattices KRA Hazzard, V Gurarie, M Hermele, AM Rey, PRA 85, 041604(R) (2012) Experiments on 173Yb (N=6) Taie, R Yamazaki, S Sugawa, Y Takahashi, arxiv:1208:4883 (Nature Physics, to appear) our theory L Bonnes et al, PRL 109, 205305 (2012) Stochastic series expansion QMC (1D: no sign problem) Spin structure factor related: L Messio and F Mila arxiv:1207.1320 log10(density [cm-3]) Carr, DeMille, Krems, Ye, New. J. Phys. 2009. Novel phases & quantum many-body Dipolar quantum gas 12 Quantum information Ultracold Chemistry Molecule optics & circuitry Cold controlled chemistry 9 Phase space density Novel collisions Fundamental tests Precision measurement 6 log10(temperature [K]) 3 -9 -6 -3 0 40K Temperature ~ 160 nK T/TF = 1.4 Density ~1012/cm3 r ~ 0.1 Fermions K. Ni et al., Science 322, 231 (2008). 87Rb Bosons KRb molecules (Dipole ~0.5 Debye) 3D gas Fast decay rates: millisecond lifetime Ospelkaus et al., Science (2010). K.-K. Ni et al., Nature (2010). Solution 2D quantum gas M. de Miranda, et al.,Nat. Phys. 7, 502 (2011). Lifetime~ 1 second E Further Suppression 3D lattice 0D gas Low density: filling ~0.1-0.2 1D gas A. Chotia et al PRL 108, 080405 (2012). Use rotational degrees of freedom as effective spin degrees of freedom. N:rotation N=1 | N=0 H i, j Select two dressed levels : Effective spin ½ system | 1 3 cos 2 ij | ri rj | 3 J S S z z i Ising z j ( dipole moment J S S S S x i x j Flip-flop A. Gorshkov et al: PRL.107.115301(2011) PRA 84,033619 (2011) y i y j ) Even at current filling dipolar interactions should be visible in K. Hazzard et al , arxiv:1209.4076 Ramsey spectroscopy 1D system, DMRG solution Tipping angle dependence p/10 Use split electric field plates to independently control E & gradient. Vertical E field polarizes KRb; Radial E-field gradient tilts the trap. -V -(V+dV) V V + dV In 2D, TF N , Log(N)/Log(T) < 2 means increasing PSD. KRb Number (x 103) 30 30 10 10 3 E=0, anti-evaporate time 3 Log(N)/Log(T) = 2.3 1 0.2 0.22 0.24 1 30 E = 3.4 kV/cm 10 10 3 3 0.2 0.3 0.4 0.5 0.6 0.7 0.3 0.4 0.5 0.6 E = 4.3 kV/cm Log(N)/Log(T) = 1.2 Log(N)/Log(T) = 1.5 1 E gradient ~ 40 V/cm2 Log(N)/Log(T) = -5 0.18 30 E = 2.8 kV/cm 1 0.15 Temperature (mK) 0.2 0.25 0.3 0.35 Decrease T/TF by 20% Electric field OH HCO H2CO H2O Stuhl et al., arXiv:1209.6343 ,Nature, in press (2012). Cooling by at least an order of magnitude in temperature and three orders in phase space density!! MW Hummon, Yeo, Stuhl, Collopy, Xia, Ye, arXiv:1209.4069 Reach final T ~2 m K Theory: M. Foss-Feig K. Hazzard S. Manmana A. Gorshkov S. Wessel and L. Bonnes M. Hermele V. Gurarie J. Bohn, G. Quemener, P. Julienne, J. v. Stecher The Sr team: The KRb team: D. Jin Jun Ye M. Swallows, M. Martin, M. Bishof,S Blatt, X. Zhang, C. Benko OH – YO team: B. Yan, B. Neyenhuis, S. Moses, B. Gadway, J. Covey B. Stuhl, M.Hummon, M. Yeo