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arXiv · 0704.3796

Coherent control of broadband vacuum squeezing

Simon Chelkowski·Henning Vahlbruch·Karsten Danzmann·Roman Schnabel
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Abstract

We present the observation of optical fields carrying squeezed vacuum states at sideband frequencies from 10Hz to above 35MHz. The field was generated with type-I optical parametric oscillation below threshold at 1064nm. A coherent, unbalanced classical modulation field at 40MHz enabled the generation of error signals for stable phase control of the squeezed vacuum field with respect to a strong local oscillator. Broadband squeezing of approximately -4dB was measured with balanced homodyne detection. The spectrum of the squeezed field allows a quantum noise reduction of ground-based gravitational wave detectors over their full detection band, regardless of whether homodyne readout or radio-frequency heterodyne readout is used.

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Simon Chelkowski, Henning Vahlbruch, Karsten Danzmann, Roman Schnabel. 2007-04-28. Coherent control of broadband vacuum squeezing. https://doi.org/10.1103/physreva.75.043814

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