PC-3-2
Linear Optical Response from the Odd-Parity Bardasis-Schrieffer Mode in Locally Non-Centrosymmetric Superconductors
15:30-15:45 28/11/2023
*Changhee Lee1,2, Suk Bum Chung3,4
1. Department of Physics, University of Otago, P.O. Box 56, Dunedin 9054, New Zealand
2. Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea
3. Department of Physics and Natural Science Research Institute, University of Seoul, Seoul 02504, Korea
4. School of Physics, Korea Institute for Advanced Study, Seoul 02455, Republic of Korea
On the recent report of a field-induced first order transition in the superconducting state of CeRh2As2, which is a possible indication of a parity-switching transition of the superconductor, the microscopic physics is still under investigation. However, if two competing paring channels of opposite parities do exist, a particle-particle collective mode referred to as the Bardasis-Schrieffer (BS) mode should generically exist below the pair-breaking continuum. The BS mode of the CeRh2As2 superconductor can couple to the light, as it arises from a pairing channel with the parity opposite to that of the ground state pairs. Here, by using a generic model Hamiltonian we carry out a qualitative investigation on the excitation energy of the BS mode with respect to the out-of-plane magnetic fields and its contribution to the optical conductivity. Our result shows the microwave absorption peaking at the transition as the signature of the BS mode, and hence a smoking gun signature of the parity-switching at the transition in the superconducting phase.
C. Lee, and S.B. Chung. "Linear optical response from the odd parity Bardasis-Schrieffer mode in locally non-centrosymmetric superconductors." arXiv preprint arXiv:2212.13722 (2022).
S.B.Chung was supported by the National Research Foundation of Korea (NRF) grants funded by the Korea government (MSIT) (2020R1A2C1007554) and the Ministry of Education (2018R1A6A1A06024977).
