Multi-Transparency Windows and Fano interference Induced by Dipole-Dipole Couplings

TL;DR

This paper introduces Dipole-Dipole Induced Transparency (DDIT), a phenomenon where dipole-dipole couplings create multiple transparency windows in a two-level system's optical response, similar to EIT in three-level atoms.

Contribution

The study reveals how dipole-dipole interactions induce transparency windows in coupled two-level systems, extending EIT-like effects to many-body quantum systems.

Findings

Number of TLSs equals the number of transparency windows.

DDIT scales with the number of coupled TLSs.

Physical implementation is feasible in various quantum systems.

Abstract

We investigate the optical properties of a two-level system (TLS) coupled to a linear series of $N$ other TLS's with dipole-dipole coupling between the first neighbours. The first TLS is probed by weak field and we assume that it has a decay rate much stronger than the decay rates of the other TLS's. For N=1 and in the limit of a probe field much weaker than the dipole-dipole coupling, the optical response of the first TLS, i.e., its absorption and dispersion, are equivalent to those of a three-level atomic system in the configuration which allow one to observe electromagnetically induced transparency (EIT) phenomenon. Thus, here we are investigating a new kind of induced transparency where the dipole-dipole coupling plays the same role of the control field in EIT in three-level atoms. We describe this physical phenomenon, here named as Dipole-Dipole Induced Transparency (DDIT), and investigate how it scales with the number of coupled TLS's. In particular we have shown that the number of TLS's coupled to the main one is exactly equals to the number of transparency windows. The ideas presented here are very general and can be implemented in different physical systems such as array of superconducting qubits, array of quantum dots, spin chains, optical lattices, etc.