Phase-Boundary of several Multicube Superconducting Circuits in a Magnetic-Field of Arbitrary Magnitude and Direction

Abstract

A previous study [C.-R. Hu and C.-H. Huang, Phys. Rev. B 43, 7718 (1991)] of the phase boundary T(c)(H) of a single-cube superconducting circuit in an external magnetic field H of arbitrary magnitude and direction is extended here to superconducting circuits containing 2 X 2 X 2, 4 X 4 X 4, and 6 X 6 X 6 cubes. For the last two cases, the study reported here is limited to the vicinity of one major peak of T(c)(H) only, in order to limit the total computing time. However, by going up to 6 X 6 X 6 cubes, we have practically obtained the limiting behavior, in the vicinity of this major peak studied, of an n X n X n cube circuit as n --> infinity. This result is believed to illustrate the generic behavior of all such major peaks, which, as has been noted in the earlier work of Hu and Huang, is the most important property of such circuits for most applicational purposes.