Proposal of a two-qubit quantum phase gate for quantum photonic integrated circuits

TL;DR

This paper proposes a fast, integrated photonic two-qubit quantum phase gate using quantum dots and electric field tuning, achieving high fidelity for quantum computing applications.

Contribution

It introduces a novel protocol for a two-qubit quantum phase gate utilizing quantum dot reflection and electric field control, suitable for integrated photonic circuits.

Findings

Fidelity of about 0.9 demonstrated through simulations

Gate operation based on photon reflection and quantum dot resonance tuning

Scheme compatible with integrated photonic quantum processors

Abstract

We propose a protocol for two-qubit quantum phase gate based upon reflection of photon pulses from a quantum dot in a cavity. Depending on the state of the quantum dot the reflected photons acquire a conditional phase shift. The key ingredient is the ultrafast control of the quantum dot energies by electric fields, which allows for tuning the exciton and biexciton successively into resonance with the cavity mode. The complete dynamics of the gate are simulated revealing a fidelity of about 0.9. The proposed scheme uses position-coding and is therefore well suited to the implementation in an integrated photonic quantum processor.