Absence of Cyclotron Resonance in the Anomalous Metallic Phase in InOx

Youcheng Wang, I. Tamir, D. Shahar, N. P. Armitage
2018 Physical Review Letters  
It is observed that many thin superconducting films with not too high disorder level (generally R$_N/\Box \leq 2000 \Omega$) placed in magnetic field show an anomalous metallic phase where the resistance is low but still finite as temperature goes to zero. Here we report in weakly disordered amorphous InO$_x$ thin films, that this "Bose metal" metal phase possesses no cyclotron resonance and hence non-Drude electrodynamics. Its microwave dynamical conductivity shows signatures of remaining
more » ... s of remaining short-range superconducting correlations and strong phase fluctuations through the whole anomalous regime. The absence of a finite frequency resonant mode can be associated with a vanishing downstream component of the vortex current parallel to the supercurrent and an emergent particle-hole symmetry of this anomalous metal, which establishes its non-Fermi liquid character.
doi:10.1103/physrevlett.120.167002 pmid:29756920 fatcat:55xp62ttcbgazfxg3r3quscxju