Tailorable couplings of a cantilever with a superconducting charge qubit: Quantum state engineering

TL;DR

This paper presents a theoretical method to engineer tunable couplings between a cantilever and a superconducting charge qubit, enabling the creation of nonclassical quantum states and analyzing environmental effects on these states.

Contribution

It introduces a scheme for adjustable couplings allowing quantum state engineering of a cantilever via a superconducting charge qubit, including state preparation and environmental impact analysis.

Findings

Able to generate superposed coherent states and squeezed states of the cantilever.

Environmental decoherence drives the cantilever to a steady coherent state.

Environment can induce steady-state position squeezing at critical temperatures.

Abstract

We propose a theoretical scheme to realize tailorable couplings between a cantilever and a superconducting charge qubit. By tuning the controllable parameters of the qubit, both linear and nonlinear couplings between the cantilever and the qubit can be achieved. Based on these couplings, we show the preparation of the cantilever into some interesting quantum states, such as superposed coherent states and squeezed states, via manipulating and detecting the qubit. We also study the influence of the environment on quantum states of the cantilever. It is indicated that decoherence induced by the environment can drive the cantilever from superposed coherent states into the steady coherent state. It is also found that the environment can induce the steady-state position squeezing of the cantilever under a critical temperature. These results will shed new light on production of nonclassical effects of the cantilever.