Fast Two-Qubit Gates in Semiconductor Quantum Dots using a Photonic Microcavity

TL;DR

This paper presents a novel design for fast, long-range two-qubit gates in semiconductor quantum dots mediated by a photonic microcavity, enabling scalable quantum computing with high fidelity.

Contribution

The authors introduce a new design for two-qubit gates that does not require identical qubits and is compatible with existing single-qubit operations, advancing scalable quantum architectures.

Findings

Gate fidelity can exceed 90% in accessible systems.

Design enables long-range two-qubit operations without identical qubits.

Compatible with current optically induced single-qubit operations.

Abstract

Implementations for quantum computing require fast single- and multi-qubit quantum gate operations. In the case of optically controlled quantum dot qubits theoretical designs for long-range two- or multi-qubit operations satisfying all the requirements in quantum computing are not yet available. We have developed a design for a fast, long-range two-qubit gate mediated by a photonic microcavity mode using excited states of the quantum dot-cavity system that addresses these needs. This design does not require identical qubits, it is compatible with available optically induced single qubit operations, and it advances opportunities for scalable architectures. We show that the gate fidelity can exceed 90% in experimentally accessible systems.