Critical behavior of resistivity in the pressure-induced first to second order transition in Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B=Co and Cr) polycrystals

Journal Article · Wed Jun 24 00:00:00 EDT 2015 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.4917588· OSTI ID:22490186

Thiyagarajan, R.; Mahendiran, R. ^[1]

---

1. Department of Physics, 2 Science Drive 3, Faculty of Science, National University of Singapore, Singapore-117551 (Singapore)

We have investigated the hydrostatic pressure (P) dependence of the resistivity on Pr{sub 0.6}Ca{sub 0.4}Mn{sub 0.96}B{sub 0.04}O{sub 3} (B = Co and Cr) polycrystals. At ambient pressure, the temperature dependence of resistivity [ρ(T)] of both the samples show a first order paramagnetic insulator-ferromagnetic metallic transition at T=T{sub IM}. The application of P on both the samples increases the T{sub IM}, reduces the resistivity, and suppresses the hysteresis width, indicating a crossover from first to second order transition. The critical pressure, where the first-second order crossover takes place, are 2.02 and 2.40 GPa for Co and Cr doped samples respectively. The critical property of both systems around second order transition is investigated using Fisher-Langer relation and Suezaki-Mori method. The estimated critical exponents are close to the three-dimensional Heisenberg model for the Co doped sample suggesting short range interaction, and the exponents for the Cr doped sample follow the mean field theory suggesting long range ferromagnetic order. Further, the application of P suppresses the high temperature resistivity by reducing high temperature polarons in the case of the Cr doped sample, but it does not happen for the Co doped sample. The application of P helps to examine the stability of polarons in the high temperature regime.

• OSTI ID: 22490186
• Journal Information: AIP Conference Proceedings, Vol. 1665, Issue 1; Conference: 59. DAE solid state physics symposium 2014, Tamilnadu (India), 16-20 Dec 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CALCIUM COMPOUNDS
CHROMIUM COMPOUNDS
COBALT COMPOUNDS
CRITICAL PRESSURE
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
HEISENBERG MODEL
HYSTERESIS
INTERACTION RANGE
MANGANATES
MEAN-FIELD THEORY
PARAMAGNETISM
PHASE STABILITY
POLARONS
POLYCRYSTALS
PRASEODYMIUM COMPOUNDS
PRESSURE DEPENDENCE
PRESSURE RANGE GIGA PA
TEMPERATURE DEPENDENCE
THREE-DIMENSIONAL LATTICES