Hardware

Photonic Qubits: Computing at the Speed of Light

Explore linear optical quantum computing where photons serve as information carriers, offering scalability and room-temperature operation.

QWiki Team 1 min read
#hardware#optics#photons#silicon-photonics
Explore Labs

Introduction

Photonic quantum computing uses light particles (photons) as the qubits. Optical components like beam splitters, phase shifters, and mirrors are arranged on silicon photonic chips to process quantum information.

Advantages

  1. No Cryogenics Needed for Qubits: Photons do not interact with the thermal environment, meaning the qubits themselves can operate at room temperature.
  2. Low Decoherence: Photons rarely interact with each other or the environment, avoiding decoherence.
  3. Networking Integration: Photons are the ideal medium for quantum communication, making photonic computers natively ready for quantum networks.

The Challenges

Because photons do not interact with each other, creating two-qubit gates (which require state interaction) is extremely difficult. Photonic architectures overcome this using:

  • Measurement-Based Quantum Computation (MBQC): Large entangled states of light (cluster states) are prepared, and computation is carried out by sequentially measuring individual photons.