Directionally Unbiased Linear-Optical Multiports for Quantum Information Processing
Alexander V. Sergienko, David S. Simon, Casey A. Fitzpatrick · Conference on Lasers and Electro-Optics · 2017
The concept of directionally unbiased optical multiport is introduced, in which photons may reflect back out the input direction. It acts as universal qubit and Bell-state processor to implement probabilistic quantum gates.