Measurement of the expectation values of the photon annihilation and creation operators themselves

Kouji Nakamura, Masa-Katsu Fujimoto

Published 2017-09-06Version 1

Motivated by the readout scheme in interferometric gravitational-wave detectors, we consider the device which measures the expectation value of the photon annihilation and creation operators themselves. As the result, the eight-port homodyne detection is rediscovered as this device which enables us to measure the expectation values of annihilation and creation operators for output optical field from the main interferometer. We also evaluate the noise spectral density in this measurement. We call this measurement scheme to measure these expectation values as "double balanced homodyne detection."