Abstract
We present the observation of optical fields carrying squeezed vacuum states at sideband frequencies from to above . The field was generated with type-I optical parametric oscillation below threshold at . A coherent, unbalanced classical modulation field at 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 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.
1 More- Received 18 October 2006
DOI:https://doi.org/10.1103/PhysRevA.75.043814
©2007 American Physical Society