Schr\"{o}dinger cats in quantum-dot--cavity systems

TL;DR

This paper explores the feasibility of creating Schrödinger-cat states in solid-state quantum-dot--cavity systems, analyzing how environmental factors affect the coherence and proposing regimes where cat states can be maintained.

Contribution

It adapts existing photonic cat preparation protocols to quantum-dot--cavity systems and identifies conditions under which quantum coherence survives environmental disturbances.

Findings

One protocol's coherence is destroyed by environmental influences.

A parameter regime exists where Schrödinger-cat states survive realistic conditions.

Environmental effects like cavity losses and phonon interactions are critical factors.

Abstract

A Schr\"odinger-cat state is a coherent superposition of macroscopically distinguishable quantum states, in quantum optics usually realized as superposition of coherent states. Protocols to prepare photonic cats have been presented for atomic systems. Here, we investigate in what manner and how well the preparation protocols can be transferred to a solid state platform, namely a semiconductor quantum-dot--cavity system. In quantum-dot--cavity systems there are many disruptive influences like cavity losses, the radiative decay of the quantum dot, and the pure-dephasing type coupling to longitudinal acoustic phonons. We show that for one of the protocols these influences kill the quantum coherence between the states forming the cat, while for a second protocol a parameter regime can be identified where the essential characteristics of Schr\"odinger-cat states survive the environmental influences under realistic conditions.