Magnetoplasmon resonance technique to monitor two-dimensional Dirac superconductors in fluctuating regime

Abstract

We propose the magnetoplasmon resonance technique to investigate two-dimensional superconductors (taking MoS$_2$ as an example) in the fluctuating regime, where the temperature is slightly above the critical temperature of the superconducting transition. Thus, unpaired electrons and fluctuating Cooper pairs coexist in the system and interact with each other via long-range Coulomb forces, forming a Bose-Fermi mixture. We expose the sample to external time-dependent electromagnetic field with a frequency in sub-terahertz range and a permanent magnetic field, and show that the magnetoplasmon response of the system is strongly modified in the presence of superconducting fluctuations in the vicinity of the superconducting transition. In particular, the fluctuating Cooper pairs dramatically change the position and broadening of the magnetoplasmon resonance, which is reflected in the optical response of the system.