Strong and weak coupling of two coupled qubits

TL;DR

This paper provides an exact analytical study of two coupled qubits under incoherent pumping and decay, revealing new strong coupling regimes and reconstructing dressed states even with strong decoherence.

Contribution

It introduces a novel analytical framework for understanding strong coupling in a nonlinear, dissipative two-qubit system with incoherent pumping.

Findings

Identification of new strong coupling regimes due to coherence flow paths

Reconstruction of dressed states under strong decoherence

Exact analytical description of coupled qubits with pumping and decay

Abstract

I investigate the dynamics and power spectrum of two coupled qubits (two-level systems) under incoherent continuous pump and dissipation. New regimes of strong coupling are identified, that are due to additional paths of coherence flow in the system. Dressed states are reconstructed even in the regime of strong decoherence. The results are analytical and offer an exact description of strong-coupling in presence of pumping and decay in a nontrivial (nonlinear) system.