Detection of 15 dB Squeezed States of Light and their Application for the Absolute Calibration of Photoelectric Quantum Efficiency

TL;DR

This paper demonstrates the direct measurement of 15 dB squeezed vacuum states of light and uses them to calibrate the quantum efficiency of a photodiode with high precision, advancing quantum metrology.

Contribution

It presents a novel application of squeezed states for absolute calibration of photoelectric quantum efficiency without standard references.

Findings

Achieved 15 dB squeezing of vacuum states of light.

Calibrated photodiode quantum efficiency to 99.5% with 0.5% uncertainty.

Calibration method does not require incident light power knowledge.

Abstract

Squeezed states of light belong to the most prominent nonclassical resources. They have compelling applications in metrology, which has been demonstrated by their routine exploitation for improving the sensitivity of a gravitational-wave detector since 2010. Here, we report on the direct measurement of 15 dB squeezed vacuum states of light and their application to calibrate the quantum efficiency of photoelectric detection. The object of calibration is a customized InGaAs positive intrinsic negative (p-i-n) photodiode optimized for high external quantum efficiency. The calibration yields a value of 99.5% with a 0.5% (k = 2) uncertainty for a photon flux of the order 10^17/s at a wavelength of 1064 nm. The calibration neither requires any standard nor knowledge of the incident light power and thus represents a valuable application of squeezed states of light in quantum metrology.