Exact treatment of some phenomenological models of layered high-Tc superconductors

✍ Scribed by Arun K. Setty; K.K. Singh

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 350 KB
• Volume: 180
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(91)90553-b

✦ Synopsis

Existing treatments of phenomenological models of Bi and Tl based superconductors consisting of n layers of copper oxide are unsatisfactory because they ignore the important 04 terms in the free energy. An exact treatment of these models is presented, and it is shown that the condition of minimum free energy automatically excludes (n-1 ) of the n critical temperatures. The critical exponent fl of the order parameter is found to be independent of n and equal to ½ as usual in the Landau theory. The specific heat discontinuity Ac at the critical temperature is calculated as a function ofn. A meaningful comparison with experimental measurements of Ac at the moment is hindered by the limited availability of experimental results. Reliable determinations of Ac of a given series of layered superconductors will enable a check of the validity of theoretical results.