High fidelity ac gate operations of the quantum dot hybrid qubit

TL;DR

This paper demonstrates theoretically that high-fidelity ac gate operations are achievable in silicon quantum dot hybrid qubits, which are promising for scalable quantum computing due to their electrical control and GHz operation speed.

Contribution

It identifies optimal parameters and working points for ac gate control in silicon quantum dot hybrid qubits, achieving threshold fidelities for quantum error correction.

Findings

Achieves threshold fidelity with ac gate operation

Minimizes charge noise dependence in qubit frequency

Determines optimal working points for ac control

Abstract

Semiconductor quantum dots in silicon are promising qubits because of long spin coherence times and their potential for scalability. However, such qubits with complete electrical control and fidelities above the threshold for quantum error correction have not yet been achieved. We show theoretically that the threshold fidelity can be achieved with ac gate operation of the quantum dot hybrid qubit. Formed by three electrons in a double dot, this qubit is electrically controlled, does not require magnetic fields, and runs at GHz gate speeds. We analyze the decoherence caused by 1/f charge noise in this qubit, find the parameter regime for tunnel couplings and detuning that minimize the charge noise dependence in the qubit frequency, and determine the optimal working points for ac gate operations that drive the detuning and tunnel coupling.