Charge Qubit-Atom Hybrid

TL;DR

This paper proposes a hybrid quantum system combining a superconducting charge qubit with a neutral atom using electric dipole coupling, enabling controlled hybrid states and potential two-qubit gates.

Contribution

It introduces a novel interface between superconducting circuits and atomic systems via gate capacitance modulation for strong coupling.

Findings

Demonstrates electric dipole coupling between charge qubit and Rydberg atom

Shows control of hybrid quantum states through gate voltage sweeping

Proposes implementation of a universal two-qubit gate

Abstract

We investigate a novel hybrid system of a superconducting charge qubit interacting directly with a single neutral atom via electric dipole coupling. Interfacing of the macroscopic superconducting circuit with the microscopic atomic system is accomplished by varying the gate capacitance of the charge qubit. To achieve strong interaction, we employ two Rydberg states with an electric-dipole allowed transition, which alters the polarizability of the dielectric medium of the gate capacitor. Sweeping the gate voltage with different rates leads to a precise control of hybrid quantum states. Furthermore, we show a possible implementation of a universal two-qubit gate.