We report on the generation of cw squeezed vacuum states of light at the telecommunication wavelength of 1550 nm. The squeezed vacuum states were produced by type I optical parametric amplification in a standing-wave cavity built around a periodically poled potassium titanyl phosphate crystal. A nonclassical noise reduction of 5.3 dB below the shot noise was observed by means of balanced homodyne detection.
© 2009 Optical Society of America
Original Manuscript: December 2, 2008
Manuscript Accepted: February 1, 2009
Published: March 25, 2009
Moritz Mehmet, Sebastian Steinlechner, Tobias Eberle, Henning Vahlbruch, André Thüring, Karsten Danzmann, and Roman Schnabel, "Observation of cw squeezed light at 1550 nm," Opt. Lett. 34, 1060-1062 (2009)