Uniaxial pressure effect of Metal-Insulator Transition (T$_{\mathrm{MI}}$) in oriented Sm$_{0.55}$(Sr$_{0.5}$Ca$_{0.5}$)$_{0.45}$MnO$_3$

ORAL

Abstract

Perovskite type manganites $R_{1-x}A_{x}$\textit{MnO}$_{3}$ ($R$: rare earth ions, $A$: alkaline earth ions) exhibit various fundamental phenomena like colossal magnetoresistance (CMR), phase separation, and first-order ferromagnetic (FM) to paramagnetic (PM) phase transition etc. Similar to CMR, piezoresistance (PR), the change in electrical resistance in response to external pressure, can also be important parameter for various technological applications. Several studies shows that the order of phase transition can be changed either by applying external perturbations like magnetic field, pressure ($P)$, etc. or internally like doping etc. \textit{SSCMO} single crystal was grown using floating zone technique and the quality was carefully checked and aligned along the c axis as well as \textit{ab-}plane. We have investigated the effect of uniaxial pressure ($P)$ on electrical resistivity along the \textit{ab-}plane and $c-$axis in a single crystal of \textit{SSCMO}. A huge \textit{PR}$\sim $\textit{10}$^{7}$\textit{{\%}} at $P =$\textit{ 90 MPa} and a remarkable increase ($\sim $\textit{79 K/GPa}) of $T_{MI}$ have been observed with the application of $P$ \textbar \textbar $c-$axis, while $T_{MI}$ decreases at the rate of $\sim $\textit{77 K/GPa} for $P \quad \bot $c axis. These values of \textit{PR} and \textit{dT}$_{MI}$ \textit{/dP} are much larger than those observed in other perovskite and bilayer manganites. Hence, these materials may be used for various technological applications.

Authors

  • Arumugam S

    Centre for High Pressure Research, Bharathidasan University, Center for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, India

  • Mohan Radheep D

    Centre for High Pressure Research, Bharathidasan University, Center for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620 024, India

  • P. Sarkar

    Saha Institute of Nuclear Physics, Kolkata

  • P. Mandal

    Saha Institute of Nuclear Physics, Kolkata