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arXiv · 0707.2845

Quantum engineering of squeezed states for quantum communication and metrology

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

We report the experimental realization of squeezed quantum states of light, tailored for new applications in quantum communication and metrology. Squeezed states in a broad Fourier frequency band down to 1 Hz has been observed for the first time. Nonclassical properties of light in such a low frequency band is required for high efficiency quantum information storage in electromagnetically induced transparency (EIT) media. The states observed also cover the frequency band of ultra-high precision laser interferometers for gravitational wave detection and can be used to reach the regime of quantum non-demolition interferometry. And furthermore, they cover the frequencies of motions of heavily macroscopic objects and might therefore support the attempts to observe entanglement in our macroscopic world.

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Henning Vahlbruch, Simon Chelkowski, Karsten Danzmann, Roman Schnabel. 2007-07-19. Quantum engineering of squeezed states for quantum communication and metrology. https://doi.org/10.1088/1367-2630/9/10/371

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