Optical state truncation
Stephen Mark Barnett, David Thomas Pegg · Physical Review A · 1999
We investigate the effects of photodetector imperfections on a recently proposed device designed to truncate physically a state of light. We find that the mixed state produced in the presence of the imperfections has a surprisingly good fidelity with the required state. For convenience and mathematical simplicity, we make use of the quantum-mechanical retrodictive formalism but show that the results are equivalent to those obtainable from more usual predictive formalism.