Strong coupling of spin qubits to a transmission line resonator

TL;DR

This paper proposes a method to strongly couple spin qubits in double quantum dots to a superconducting resonator, enabling fast two-qubit operations and entanglement generation with minimized dephasing.

Contribution

It introduces a novel coupling mechanism via the gate controlling interdot tunneling, achieving strong interaction and facilitating quantum gate operations.

Findings

Coupling strength of tens of MHz achieved.

System operates at a degeneracy point to reduce dephasing.

Enables fast entanglement and controlled-phase gates.

Abstract

We propose a mechanism for coupling spin qubits formed in double quantum dots to a superconducting transmission line resonator. Coupling the resonator to the gate controlling the interdot tunneling creates a strong spin qubit--resonator interaction with strength of tens of MHz. This mechanism allows operating the system at a point of degeneracy where dephasing is minimized. The transmission line can serve as a shuttle allowing for two-qubit operations, including fast generation of qubit-qubit entanglement and the implementation of a controlled-phase gate.