We propose a nonlinear ac Hall effect in two-dimensional BCS single-band superconductors. Namely, a nonlinear ac transverse Hall current emerges in the superconductor interacting with an incident polarized light if a built-in dc supercurrent is present in the system. Applying the nonequilibrium Keldysh diagram technique, we calculate an ac Hall current density oscillating at double the electromagnetic field frequency. This current's strength is influenced by the inelastic relaxation rate, the dc supercurrent direction, and light polarization, with the ac current density being tunable via electron density. The ac Hall effect is unique to the superconducting state and is shaped by temperature, light frequency, and material characteristics.

中文翻译：

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二维超导体中的非线流霍尔效应


我们提出了二维 BCS 单带超导体中的非线流霍尔效应。也就是说，如果系统中存在内置直流超电流，则超导体中会出现非线流横向霍尔电流，与入射偏振光相互作用。应用非平衡 Keldysh 图技术，我们计算出以两倍于电磁场频率振荡的交流霍尔电流密度。该电流的强度受非弹性弛豫率、直流超电流方向和光极化的影响，交流电流密度可通过电子密度进行调整。交流霍尔效应是超导状态所独有的，受温度、光频率和材料特性的影响。