New Parametric Scattering in PhotorefractiveSr0.61Ba0.39Nb

Abstract

A new class of light-induced parametric scattering, not included in the conventional model, has been discovered in photorefractive Sr(0.61)Ba(0.39)Nb(2)O(6):Cr illuminated by two coherent beams. A novel model of multiwave mixing of coherent noise and transmitted light is developed to explain the new scattering phenomena. The model includes all known types and predicts a multitude of new types of parametric scattering. Generalized phase-matching conditions for parametric scattering in photorefractive crystals are proposed.

Broadband colored-crescent generation in a singleβ-barium-borate crystal by intense femtosecond pulses

“…Deviations between experiment and the calculation based on the simplified model become large at longer wavelengths for which the calculated SHG propagation direction approaches that of the pump. Such deviations are attributed to the influence from the intense pump, the potential mechanism includes the cross-phase-modulation due to pump and SHG coupling [39], parametric scattering [40,41], etc., which were not considered in our calculations. At the incident angle θ = 13 • , the calculated SHG propagation direction is far from that of the pump and the generated SHG intensity is much weaker than other incident angles [ Fig.…”

Generation of correlated UV and visible rainbows

“…2(a), parametric down-conversion was induced as axial colored cones marked as (1) in Fig.2(a), and weak abaxial conical light scatterings (2) were observed with the same color of the pump. The abaxial scattering patterns were originated from degenerate parametric light scatterings by recording gratings [15][16][17][18]. As shown in Fig.…”

“…Recently, tripartite entangled states or blue quantum-correlated light were realized in a bulk non-linear crystal according to this method [10][11][12][13][14]. On the other hand, parametric light scattering manifesting as specific light patterns are merely associated with nonlinear growth of coherent noises [15][16][17][18], while nonlinear growth of certain vacuum modes may be induced by modulational instability [19,20] but typically happens under strong pump and thus hardly applicable to quantum information processing at single-photon level. It is also difficult to generate tunable correlated photons in the UV region for multipartite entanglement experiments [21].…”

“…All these observations suggest cascaded parametric characteristics of the observed rainbows. Such processes may not only provide unique fingerprints for various nonlinear optical phenomena such as parametric scatterings and photo-charge transportation [15][16][17][18], but also support the generation of multiple angularly-resolved twin photons in the up-conversion and down-conversion regions with advantageous features inherited from both photonic cascades [22,23] and parametric processes [24], entailing a broadband tunable range and small beam divergence confined by the photon energy and momentum conservation. Multi-wavelength correlated photon pairs could thus be selected at continuously tunable wavelengths along different positions of the rainbows, and a fine wavelength-tuning of twin photons is anticipated to reach some specific atomic or molecular resonances.…”

Photorefractive parametric scattering in the ferroelectric relaxor SBN: Phenomenological and application aspects

“…In this paper we complete the phenomenological model of new parametric scattering found in SBN 25 and discuss all possible 4WM processes which may result in the scattering. An experimental study of the new 4WM processes is carried out with an example of scattering lines with even indices j observed in a low-doped SBN:Cr crystal.…”