Vacuum Squeezing of Solids: Macroscopic Quantum States Driven by Light Pulses
Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states.
Garrett
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G. A. Garrett, A. K. Sood, R. Merlin, Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI 48109-2099, and Department of Physics, University of Michigan, Ann Arbor, MI 48109-1120, USA. A. G. Rojo, Department of Physics, University of Michigan, Ann Arbor, MI 48109-1120, USA. J. F. Whitaker, Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, MI 48109-2099, USA.
Rojo
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Sood
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Whitaker
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Merlin
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