Squeezed states state generation

Equation (127) describing the evolution of the system is our starting point for further discussion of the second-harmonic generation. If the initial state of the fundamental mode is not a coherent state but has a decomposition into a number states of the form (125) with different bn, equation (127) is still valid when corresponding bn are taken. It is true, for example, for the initially squeezed state of the fundamental mode. 

This visibility is negative, indicating that the squeezing correlations stored in the antisymmetric state generate an interference pattern with a dark center. In Fig. 11, we plot the visibility f" as a function of the interatomic separation for... 

Kozhekin et al. [38] proposed a method of mapping of quantum states onto an atomic system based on the stimulated Raman absorption of propagating quantum light by a cloud of three-level atoms. Hald et al. [40] have experimentally observed the squeezed spin states of a system of three-level atoms driven by a squeezed held. The observed squeezed spin states have been generated via entanglement exchange with the squeezed held completely absorbed in the process. Fleishhauer et al. [39] have considered a similar system of three-level atoms and have found that quantum states of single-photon helds can be mapped onto collective states of the atomic system. In this case the quantum state of the held is stored in a dark state of the collective states of the system. 

A possibility of generating the nonclassical (in particular, squeezed) states of the electromagnetic field in the cavity with moving walls was pointed out in several studies in [106,114,124,158-161], The dynamical Casimir force has been interpreted as a mechanical signature of the squeezing effect associated with the mirror s motion [123,125] (see also Ref. 162). 

The creation of photons or specific (e.g., squeezed) states of the electromagnetic held due to the motion of some effective mirrors made of the free electrons moving with (ultra)relativistic velocities was studied [206-207]. Another kind of effective moving mirror consisting of the electron-hole plasma generated in semiconductors under the action of powerful laser pulses was also suggested [208,209]. 

Fig. 9.99 Generation of squeezed states by four-wave mixing in an atomic Na beam. Both the pumped wave and signal and idler waves are resonantly enhanced by two optical resonators [1335]...

R.E. Slusher, L.W. Holberg, B. Yorke, J.C. Mertz, J.F. Valley, Observation of squeezed states generated by four wave mixing in an optical cavity. Phys. Rev. Lett. 55, 2409 (1985)... 

M. D. Levenson, R. M. Shelby, A. Aspect, M. Reid and D. F. Walls. Generation and detection of squeezed states of light by nondegenerate four-wave mixing in an optical fiber. Physical Revew A 1985 Sep 32(3) 1550-1562. 

R. E. Slusher, L. W. Hollberg, B. Yurke, J. C. Mertz, and J. F. Valley. Observation of Squeezed States Generated by Four-Wave Mixing in an Optical Cavity. Physical Review Letters 1985 Nov 25 55(22) 788-788. 

A more far-reaching phenomenon is the possibility of generating radiation in "squeezed" states [4.19]. Such radiation exhibits reduced noise below the quantum limit and could have important applications for optical communication and precision interferometric measurements of small displacements, e.g. in gravity-wave detection experiments. A considerable degree of "squeezing" has recently been experimentally demonstrated [4.20, 21]. Various aspects of modern quantum optics have been discussed in [4. 22-25]. 

Kupriyanov, D.V. and Sokolov, I.M. (1991). Generation of squeezed electromagnetic field states on interaction between radiation and optically oriented atoms, Zhumal Eksperimental noi i Teoreticheskoi Fiziki, 99, 93-106. [SW Phys.—JETP, 72, 50-57]. 

The feeblest type of chemical interaction occurs between neutral atoms, not in their valence state, and is typified by inert-gas crystals. In this case the atoms occur close-packed with a very small accumulation of charge on the interstitial sites. These charges are generated by mutual polarization of vibrating atomic charge spheres. Under high pressure an increased amount of valence density is squeezed into interstitial sites until a metal structure is formed. 

However, we concentrate here on the generation methods in which we are able to get directly the FD quantum state desired. Namely, we shall describe the models involving quantum nonlinear oscillator driven by an external field [11-13,22]. For this class of systems we are able to get the quantum states that are very close for instance, to the FD coherent states [2,3] or to the FD squeezed vacuum [10]. 

The method described in the previous sections can be easily generalized to be useful for generation of various FD quantum-optical states different from the FD coherent state. Thus, we shall show an example of how to adapt our method to generate the FD squeezed vacuum [10]. In the first part of this work [see Eq. (78) in Ref. 1], we have defined the (,v + 1)-dimensional generalized squeezed vacuum to be... 

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