A d-Wave Boson-Fermion Model for High-Tc Superconductivity

• Main Authors: Shan, Chung-Lin, 單中林
• Other Authors: Chung-Yu Mou
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/45358611791718068835

碩士 === 國立清華大學 === 物理學系 === 85 === We extend the boson-fermion model of superconductivity proposed by Friedberg and Lee to incorporate the recently observed d-wave gap in high temperature superconductors. The spin of the boson field is generalized to be 2. By appropriately choosing coupling constants, a d-wave energy gap, dx^2-y^2, can be reproduced. We further derive the gap equations and the heat capacity near zero temperature. The heat capacity shows a characteristic behavior of T^2ln(T) near T=0. We also calculate the critical field; in particular, our result implies that when crossing the critical temperature Tc, the change of the specific heat is not a finite jump, but is infinite.