Phys.org July 12, 2022
Odd-parity superconductivity is rare in nature; only a few materials support this state, and in none of them has the expected angle dependence been observed. CeRh2As2 was recently found to exhibit two superconducting states: A low-field state changes into a high-field state at 4 T when a magnetic field is applied along one axis. Through a comprehensive study of the angle dependence of the upper critical fields using magnetic ac susceptibility, specific heat, and torque on single crystals of CeRh2As2 an international team of researchers (Germany, New Zealand, France, USA – University of Wisconsin) has shown that the angle dependence in the superconductor CeRh2As2 is exactly that expected of an odd-parity state. For varying field directions, they measured the specific heat, magnetic susceptibility, and magnetic torque of the material to obtain the angle dependence of the critical fields. They found that the high-field state quickly disappeared when the magnetic field was turned away from the initial axis. These results are in agreement with their model identifying the two states with even- and odd-parity states. According to the researchers the work presents an opportunity to investigate odd-parity superconductivity allows for testing mechanisms for a transition between two superconducting states, and their relation to spin-orbit coupling, multiband physics, and additional ordered states occurring in this material…read more. TECHNICAL ARTICLEÂ
A proof of odd-parity superconductivity. Credit: Phys. Rev. X 12, 031001, 1 July 2022Â