Ultrasensitive pulsed, balanced homodyne detector: application to time-domain quantum measurements.
A pulsed, balanced homodyne detector has been developed for precise measurement of the electric field quadratures of pulsed optical quantum states. A high level of common mode suppression (>85 dB) and low electronic noise (730 electrons per pulse) provide a signal-to-noise ratio of 14 dB for measurement of the quantum noise of individual pulses. Measurements at repetition rates as high as 1 MHz are possible. As a test, quantum tomography of the coherent state was performed, and the Wigner function and the density matrix were reconstructed with 99.5% fidelity. The detection system can be used for ultrarsensitive balanced detection in cw mode, e.g., for weak absorption measurements.
Hansen
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H
Aichele
T
T
Hettich
C
C
Lodahl
P
P
Lvovsky
A I
AI
Mlynek
J
J
Schiller
S
S