5
4
Ravi L. Hadimani 1* , Joao H. B. Silva 2* , Andre M. Pereira 3 , Devo L. Schlagel 4 , Thomas A. Lograsso 5 ,
Yang Ren 6 , Xiaoyi Zhang 6 , David C. Jiles 1 and Joao P. Araújo 2#
* - Both authors contributed equally to this work
1 Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011,
USA Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
2 IFIMUP and IN-Institute of Nanoscience and Nanotechnology, Departamento de Física e
Astronomia da Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, 687, 4169-
007 Porto, Portugal
3 Blackett Laboratory, Imperial College, London SW7 2AZ
4 Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
5 Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, USA
Division of Materials Science and Engineering, Ames Laboratory, Ames, Iowa 50011, USA
6 X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA

# Corresponding author: jearaujo@fc.up.pt
Thin film deposition: A multigrain sample of Gd
5
Si
1.3
Ge
2.7
prepared from high purity materials by Tri-arc method was used as a target material in a pulsed laser deposition
(PLD) system. A femtosecond laser with the pulse energy of 3.5mJ and a repetition rate of
1000 Hz was used in the PLD system. The film was deposited on a 1μm SiO
2
layer on the top of a (001) silicon substrate at 200° C and 1.2×10 6 torr. The rate of deposition was about
20 nm/sec. The use of a femtosecond laser with higher repetition rate caused coulomb ablation due to multi-photon absorption or coulomb explosion.
Characterization: In the SEM/EDS analysis, the maximum accelerating voltage of the electron beam was determined to be 15 kV. K line of Germanium and Silicon (9.8 kV and 1.74kV, respectively) and L line of Gadolinium (6.05kV) were considered for composition calculations. To estimate the chemical stoichiometry, Monte-Carlo simulation software was used to determine the maximum acceleration voltage of the beam that does not penetrate the deposited film and reach the silicon dioxide on silicon substrate during
EDS analysis.
All magnetic measurements were performed at the superconducting quantum interference device (SQUID) from Quantum Design. The magnetization temperature dependency was measured first on cooling and then on heating in the [10, 300] K

temperature range with a constant 1000 Oe magnetic field. The rate of cooling and heating was the same and equal to 2.333 K / min. Afterwards, the film was cooled again to 5K, in order to measure the M vs H curve at this temperature. The M vs H isothermal curves were measured according with the loop method 1 in the [135, 275] K temperature range, with increasing and decreasing field and a step of ~ 1250 Oe.
Synchrotron x-ray diffraction measurements of the thin film sample were carried out at the beamline 11-ID-D, Advanced Photon Source, Argonne National Laboratory. The wavelength of the x-rays was 0.765335 Å, and an Oxford cryostream system was used for the temperature dependent measurements. Two dimensional diffraction patterns were collected using a Pilatus area detector, and converted to the conventional one-dimensional diffraction curves using the Fit2D program.

Magnetocaloric effect of a set of thin film materials presenting the highest Ι ΔS m
Ι
MAX reported so far in the literature.
Chemical Composition Thickness nm
Gd
5
Si
1.3
Ge
2.7
788
Gd
5
Si
1.3
Ge
2.7
Gd
5
Si
1.3
Ge
2.7
788
788
Gd
5
Si
1.3
Ge
2.7
Gd
5
Si
1.3
Ge
2.7
W/Gd/W
W/Gd/W
Ta/Gd/Ta
La
0.7
Sr
0.3
MnO
3
/SrRuO
3
NiMnGa
NiMnGa
NiCoMnIn
La
0.67
Sr
0.33
MnO
3
//
SrTiO
3
La
0.67
Sr
0.33
MnO
3
//
SrTiO
3
MnAs
MnAs
La
0.56
Sr
0.44
MnO
3
20
70
70
31
788
788
5/40/5
5/40/5
5/30/5
8
400
400
300
20
ΙΔS m
Ι
MAX
J K -1 Kg -1
8.83
* (13.6)
7.2
* (11.09)
5.7
* (8.8)
3.7
* (5.7)
1.6
* (2.5)
~1.4
3.2
1.6
2.35
1.7
8.5
< 5
1.1
1.54
4
17
0.3
190
190
190
190
275
275
285
325
346
346
353
321
321
300
300
270
T
0 ᵻ
K
190
RCP Reference
J Kg -1
32
*50
~52
~240
~70
~125
212
*323
156
*241
121
*187
75
*116
This work
This work
This work
This work
This work
2
2
3
4
-
170
<200
~15
5
5
6
7
50 7
>120
774
~10
8
8
9
2
1
1
6
6
1
1
2
1
3
4
3
1.5
1
5
1
ΔH
T
5

La
0.56
Sr
0.44
MnO
3
FeRh
31
100
2
20
Table T1
270
320
6
5
185
431
9
10 ᵻ T
0
is the temperature where the –ΔSm(T) reaches its maximum, -ΔSm
MAX
.
* Represents the values corrected to the efficient O(II) volume fraction that contributes to –ΔSm.
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3559 (2009).
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3 H.F. Kirby, D.D. Belyea, J.T. Willman, and C.W. Miller, J. Vac. Sci. Technol. A Vacuum, Surfaces, Film.
31 , 031506 (2013).
4 Q. Zhang, S. Thota, F. Guillou, P. Padhan, V. Hardy, a Wahl, and W. Prellier, J. Phys. Condens. Matter 23 ,
052201 (2011).
5 V. Recarte, J.I. Pe ́rez-Landazábal, V. Sánchez-Alárcos, V.A. Chernenko, and M. Ohtsuka, Appl. Phys. Lett.
95 , 141908 (2009).
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Supplementary Figure S1
Supplementary Figure S1: Magnetization as a function of temperature on cooling (black curve) and on heating (red curve). The thermal hysteresis is highlighted in blue. A magnified M(T) curve is presented in the inset where the transitions are signaled with T
MS c
~ 175.9 K and T
MS h
~ 180.1 K, which were determined by the averaged maximum of the derivative of the curves. Hence, the observed thermal hysteresis is ΔT
MS
= T
MS h
- T
MS c
~4.2
K.

Supplementary Figure S2
Supplementary Figure S2: Magnetization isotherms [ M(H) ] measured in the [165, 195]
K temperature range with a 5 K step, with increasing (lower curves) and decreasing (upper curves) applied magnetic fields in the [0, 50 ] kOe interval. The hysteresis is highlighted in color and is close to zero for the T = 165 and 170 K and reaches a maximum for the T =
180 K isotherm.