Magnetocaloric Effect and Refrigerant Capacity of Non-Stoichiometric ${\rm Nd}_{0.5}{\rm Sr}_{0.5}{\rm MnO}_{3}$ Single Crystalline

Non-stoichiometric Nd
_0.5
Sr
_0.5
MnO
₃
(NSMO) single crystalline has been grown by the floating zone method. Their magnetic properties, magnetocaloric effect (MCE) and refrigerant capacity (
RC
) at near both first- and second-order phase transitions were investigated. The NSMO system goes through an antiferomagnetic charge-ordered transition at
T
_CO
~ 152 K followed by a ferromagnetic to paramagnetic transition at
T
_C
~ 272 K. The transition region spread over a broader temperature range at the
T
_C
but it had a narrower temperature range at the
T
_CO
. The maximum magnetic entropy change Δ
S
_max
gives about 1.65 J · kg
^-1
· K
^-1
at the first order magnetic transition and -1.13 J · kg
^-1
· K
^-1
at the second order magnetic transition, respectively.
RC
is obtained and it shows much higher value about 34.85 J/kg at
T
_C
than the
RC
19.06 J/kg at
T
_CO
. The slight non-stoichiometric NSMO single crystalline system raises the Curie temperature around 30 K towards room temperature without degradation of the
RC
and temperature span corresponding to the full width at half maximum of Δ
S
_max
(Δ
T
_FWHM
) compared to pure single crystalline NSMO system.