Researchers in the lab of Professor JT Shen at Washington University have developed a two-photon controlled-phase quantum logic gate capable of up to 97% fidelity at room temperature. The design uses chiral optical waveguides with photonic molecules to create a deterministic controlled-phase gate.
While electromagnetically induced transparency can be used to create deterministic gates in ultracold systems, only probabilistic gates have been demonstrated at room temperature. A high-fidelity controlled-phase gate in moderate conditions will enable fully scalable quantum architecture.
Schematic diagram of the two-photon controlled-phase gate.
Stage of Research
The inventors have designed and validated the gate computationally. Ongoing work involves constructing and testing the gate experimentally.
- Chen Z, Zhou Y, Shen J-T, Ku P-C, & Steel D. (2021). Two-photon controlled-phase gates enabled by photonic dimers. Physical Review A, 103:052610.
- Jefferson B. (2021). A new piece of the quantum computing puzzle. The Source, Washington University in St. Louis.
- Optical quantum computing
- Capable of functioning at room temperature
- Highly efficient: deterministic gate has fidelity up to 97%