Optically excited secondary emission spectra of photonic crystals based on synthetic opals

Quantum Optics and Laser Experiments

Dergachov²

2012

Quantum Optics and Laser Experiments 88 allows modifying optical properties of such systems by filling the pores with various substances. Synthetic opal photonic crystals containing nonlinear optical substances give a good chance to observe quantum optics phenomena in spatially nonuniform media where the photon mean free path is close to the light wavelength. Moreover, in this case the input optical power that is necessary to observe phenomena may be lower than the power required usually for observing the same phenomena in uniform nonlinear substances. The reason for it is the existence of diffuse transfer of photons that can result in photon accumulating inside photonic crystals and, consequently, in local optical power increasing. In particular, the possibility of experimental manifestation of Raman scattering and spontaneous parametric down-conversion in synthetic opals is discussed (Gorelik, 2007). The latter phenomenon is of special interest as it is convenient method to obtain bi-photon fields consisting of correlated photon pairs (Kitaeva & Penin, 2005). In the recent years, crystals with chirped structure of quadratic susceptibility (Kitaeva & Penin, 2004), and materials with spatially regular and stochastic distribution of quadratic optical susceptibility (Kalashnikov et al., 2009), are considered as sources of bi-photons. It is quite possible synthetic opal photonic crystals will be ranked with these sources.

“…Luminescence spectra of laser dyes (rhodamine 6G and pironin G) are shown in Fig. 7 ( Moiseyenko et al, 2008Moiseyenko et al, , 2010. As seen from Fig.…”

Section: Laser Dyes Moleculesmentioning

confidence: 95%

Quantum Optics Phenomena in Synthetic Opal Photonic Crystals

Quantum Optics and Laser Experiments

Dergachov²

2012

“…Owing to possibility for changing their optical properties by infiltrating them with various substances, these materials have long been under extensive experimental study [4][5][6]. The emission of initial synthetic opal photonic crystals (SOPC) observed under ultraviolet excitation has been interpreted in terms of enhanced Raman and parametric scattering [7,8]. At this time, similar opal emission under 400 nm dye laser excitation has been explained by the impurity luminescence [9].…”

Section: Introductionmentioning

confidence: 99%

The possibility for surface-enhanced Raman scattering and spontaneous parametric down-conversion by globular photonic crystals infiltrated with dielectrics

Dergachov²,

Shvachich³

et al. 2009

Ukr. J. Phys. Opt.

Emission of globular SiO 2 photonic crystals infiltrated with dielectrics is observed within a wide spectral region under excitation with the light wavelength λ = 400 nm. The first part of the emission spectrum located in the vicinity of the excitation line depends on infiltrated substance and is explained by surface-enhanced Raman scattering effect. The second one lying in the region of 440-650 nm that includes the stop-band is caused by spontaneous parametric down-conversion. PACS:78.67-n + 78.55.Mb UDC: 535.361

“…Besides, promising possibilities for creating highperformance light emitting diodes and laser diodes, liquid-based lasers with ultra-short pulses, and bistable optical storage cells have been demonstrated with the materials mentioned above [12][13][14][15]. Preliminary studies of the fluorescence spectrum for the BBHQ embedded in the film synthetic opal have been performed in the work [16] under excitation out of the fundamental absorption bands. To the best of our knowledge, no systematic studies of the fluorescence of photo-reactive substances placed in the synthetic opal pores have been reported in the literature.…”

Section: Introductionmentioning

confidence: 99%

Modification of optical properties of 2,5-bis(2-benzoxazolyl)hydroquinone in opal photonic crystals

Dergachov²,

Sal³

et al. 2013

Ukr. J. Phys. Opt.

Abstract. We study angular dependences of the reflection and fluorescence spectra for the synthetic opal infiltrated with a photo-reactive substance, 2,5-bis(2-benzoxazolyl)hydroquinone (BBHQ). The peak shift observed in the reflection spectra with increasing incidence angle of light is satisfactorily described by the Bragg diffraction law if the effective dielectric constant of the composite obtained by us is taken to be ε eff = 2.10. A suppression of fluorescence inside the stop-band and an increase in the shorter-wavelength fluorescence intensity are identified. The latter effect is explained by increasing role of radiative transitions through the surface states and impurity levels. The concentration of surface states increases essentially for the BBHQ embedded in the opal pores, and the impurity levels are formed by BBHQ molecules with substituted hydroxyl groups or with modified benzazole rings.