Magnetic-field-induced polarity oscillation of superconducting diode effect
Ryo Kawarazaki, Hideki Narita, Yuta Miyasaka, Yuhei Ikeda, Ryusuke Hisatomi, Akito Daido, Yoichi Shiota, Takahiro Moriyama, Youichi Yanase, Alexey V. Ognev, Alexander S. Samardak, Teruo Ono
Abstract
Abstract Recently, an ultimate diode effect, a superconducting diode where an electric current shows the superconducting state in one direction and the normal state in the other direction, has been discovered in a noncentrosymmetric Nb/V/Ta superlattice. Here, we report that the polarity of the superconducting diode shows a sign reversal as a magnetic field is increased. Such a nonlinear behavior of the diode effect is beyond the phenomenology based on the Ginzburg–Landau theory. Based on a recent microscopic study, we propose the crossover and phase transitions of the finite-momentum pairing states as a possible origin of the sign reversals.