Phase transitions in Lu{sub 2}Ir{sub 3}Si{sub 5}

Journal Article · Sat Jan 15 00:00:00 EST 2005 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.71.045109· OSTI ID:20665065

Singh, Yogesh; Pal, Dilip; Ramakrishnan, S; Malik, S K ^[1]; Awasthi, A M ^[2]

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1. Tata Institute of Fundamental Research, Bombay-400005 (India)
2. IUC-DAEF, Indore-452017 (India)

We report the results of our investigations on a polycrystalline sample of Lu{sub 2}Ir{sub 3}Si{sub 5}, which crystallizes in the U{sub 2}Co{sub 3}Si{sub 5}-type structure (Ibam). These investigations comprise powder x-ray diffraction, magnetic susceptibility, electrical resistivity, and high-temperature (120-300 K) heat-capacity studies. Our results reveal that the sample undergoes a superconducting transition below 3.5 K. It also undergoes a first-order phase transition between 150-250 K as revealed by an upturn in the resistivity, a diasmagnetic drop in the magnetic susceptibility, and a large anomaly (20-30 J/mol K) in the specific heat data. We observe a huge thermal hysteresis of almost 45 K between the cooling and warming data across this high-temperature transition in all our measurements. Low-temperature x-ray diffraction measurements at 87 K reveals that the compound undergoes a structural change at the high-temperature transition. Resistivity data taken in repeated cooling and warming cycles indicate that at the high-temperature transition, the system goes into a highly metastable state; successive heating and/or cooling curves are found to lie above the previous one, and the resistance keeps increasing with every thermal cycle. The room-temperature resistance of a thermally cycled piece of the sample decays exponentialy with time with a decay-time constant estimated to be about 10{sup 4} s. The anomaly (upturn) in the resistivity and the large drop ({approx}40%) in the susceptibility across the high-temperature transition suggest that the observed structural change is accompanied or induced by an electronic transition.

• OSTI ID: 20665065
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 71, Issue 4; Other Information: DOI: 10.1103/PhysRevB.71.045109; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COOLING
ELECTRIC CONDUCTIVITY
HEATING
HYSTERESIS
IRIDIUM COMPOUNDS
LUTETIUM COMPOUNDS
MAGNETIC SUSCEPTIBILITY
METASTABLE STATES
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
POLYCRYSTALS
SILICON COMPOUNDS
SPECIFIC HEAT
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
X-RAY DIFFRACTION