Hardware & Errors
Photonic Qubit
A qubit implemented using properties of individual particles of light (photons), often operable near room temperature.
Definition
Photonic qubits encode quantum information using properties of light particles (photons), such as polarization or path. Unlike most other qubit types, photonic systems often don't require extreme cryogenic cooling for the qubits themselves, though some supporting components still need cooling.
Technical Definition
Some photonic platforms use discrete photon counting (true qubits), while others, like Xanadu's systems, use continuous-variable encoding with 'squeezed' states of light, representing information differently than the discrete |0⟩/|1⟩ framework used elsewhere in this dictionary.
Visual Explanation: An Analogy
Think of photonic qubits like sending information using the specific 'angle' or timing of beams of light through a maze of mirrors and optical components, rather than using electrical signals or trapped particles.
Real-World Use Cases
- Used by companies like Xanadu and in experiments like China's Jiuzhang boson sampling demonstrations
- Naturally suited to quantum networking since photons already travel through fiber optic cables
- Can operate largely at room temperature, simplifying some infrastructure requirements