Many-qubit network employing cavity QED in a decoherence-free subspace

TL;DR

This paper presents a scalable many-qubit network using cavity QED with decoherence-free encoding, enabling robust quantum gates and communication with fewer steps and resistance to collective dephasing.

Contribution

It introduces a novel cavity QED-based scheme encoding qubits in a decoherence-free subspace for efficient multi-qubit gates and communication.

Findings

Resists collective dephasing errors

Reduces implementational steps compared to conventional methods

Demonstrates feasibility with current cavity QED technologies

Abstract

We propose a many-qubit network with cavity QED by encoding qubits in decoherence-free subspace, based on which we can implement many-logic-qubit conditional gates by means of cavity assisted interaction with single-photon pulses. Our scheme could not only resist collective dephasing errors, but also much reduce the implementational steps compared to conventional methods doing the same job, and we can also complete communications between two arbitrary nodes. We show the details by implementing a three-logic-qubit Toffoli gate, and explore the experimental feasibility and challenge based on currently achievable cavity QED technologies.