Interaction of a qubit with a transistor-like material*

We theoretically study a system that consists of a two-level system interacting with the two-dimensional transistor-like optical platform introduced in [1]. The optical response of the two-dimensional material is tailored by a static electric field through a non-Hermitian linear electro-optic effect rooted on a Berry curvature dipole. The dynamical response of the material mimics that of a transistor but in a distributed area. Here, we use a quasi-static approximation to describe the interactions of an elementary qubit with the transistor-like material. We obtain a quantum (Lindblad-type) master equation written in terms of the system Green’s function, taking into account that the considered platform may provide optical gain. We analyze the time-evolution of the qubit state, showing how the optical gain tailors the light-matter interactions and gives rise to rather peculiar and exotic effects such as negative spontaneous emission and time-crystal like oscillations in the ground state.

[1] T. G. Rappoport, T. A. Morgado, S. Lannebère, M. G. Silveirinha, “Engineering transistor-like optical gain in two-dimensional materials with Berry curvature dipoles”, Phys. Rev. Lett., 130, 076901, 2023.