Phase Transitions in Magnetic and Superconducting Systems with Fluctuating Valence. Chemical Potential Evidence

• Authors: E. Gosławska , M. Matlak , Kh. Eid
• Languages of publication: EN

Abstracts

EN

We investigate the critical behaviour of the chemical potential and average occupation numbers using the extended s -f model with intersite Cooper pairing for systems with fluctuating valence. The model is able to describe phase transitions from normal ferromagnet to normal paramagnet at T=T_{C}, from superconducting paramagnet to normal paramagnet at T=T_{S}, as well as reentrant phase transitions with three critical temperatures T_{S_{1}}, T_{C} and T_{S_{2}} (T_{S_{1}} < T_{C} < T_{S_{2}}). Present investigation, as well as recent results obtained for another models suggest one-to-one correspondence between critical temperatures of the system and kinks appearing in the temperature dependence of the chemical potential and average occupation numbers. This, in turn, indicates a possibility to apply the measurement of the chemical potential vs. temperature as an experimental universal tool when looking for phase transitions in solids.

Keywords

EN

75.30.Kz; 75.40.Cx

Discipline

• 75.40.Cx: Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.)
• 75.30.Kz: Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)(for ferroelectric phase transitions, see 77.80.B-; for superconductivity phase diagrams, see 74.25.Dw)

• Journal: Acta Physica Polonica A
• Year: 2000
• Volume: 97
• Issue: 4
• Pages: 713-718

Dates

published

2000-04

received

1999-11-18

Contributors

author

E. Gosławska

• Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland

author

M. Matlak

• Institute of Physics, Silesian University, Uniwersytecka 4, 40-007 Katowice, Poland

author

Kh. Eid

• Physics Department, Faculty of Education, Ain-Shams University, Roxy, Cairo, Egypt

Identifiers

DOI

10.12693/APhysPolA.97.713