Feedforward-assisted coherent-state comparison amplifier
Abstract
Quantum optical coherent-state comparison amplifiers are nondeterministic devices which can amplify rather noiselessly a weak coherent state with an unknown phase from a finite discrete set. The high fidelity and high success probability of this amplifier are accomplished by a comparison stage and some photon subtraction stages. Due to the heralding nature of these amplifiers, they work part of the time. Here, we propose a feedforward protocol to increase the heralded times by correcting the incorrect guess. Hence, we enhance the fidelity and success probability more. Finally, the schematic experimental configuration of the feedforward-assisted coherent-state comparison amplifier is proposed.
- Publication:
-
Physical Review A
- Pub Date:
- October 2019
- DOI:
- 10.1103/PhysRevA.100.043809
- Bibcode:
- 2019PhRvA.100d3809B