Conical diffraction and Bessel beam formation with a high optical quality biaxial crystal

Abstract

Abstract:The manipulation of a Gaussian laser beam using conical diffraction in a high optical quality biaxial crystal of KGd(WO 4 ) 2 has been examined in detail with emphasis on the experimental techniques involved and intuitive explanations of the notable features. Two different optical arrangements were used to form the Pogendorff double-ring light pattern in the focal image plane. The formation of both diverging and non-diverging zeroth and first order Bessel beams was investigated. The various intensity distributions and polarization properties were measured and compared with the predictions of well-established theory. 187-197 (1999). ©2009 Optical Society of America

Conical refraction: fundamentals and applications

“…As a consequence, the center of the CR beam will possess always the same SOP as the input beam. This fact, that was already pointed out in [62,63,65], will be discussed with more detail below. To obtain the Stokes parameters of the CR beam, Eqs.…”

“…Although being the case of a Gaussian input beam the most studied situation in CR for cylindrically symmetric beams [33,[61][62][63][64][65][66][67][68][69], other works have investigated CR for Laguerre-Gauss beams [70,71] and for top-hat beams [72].…”

“…The major advantage of self-healing beams is that they can be used through turbulent media [152] and that they are ideal candidates for particle manipulation at different planes [156,157] and in microscopy [158]. The CR phenomenon has been also reported as an efficient tool to generate Bessel beams [62,159,160]. The relation of CR with Bessel beams suggests that even if the input Gaussian beam is partially blocked, the CR beam may only be slightly affected.…”

Two-section singlemode lasers based on slots suitable for photonic integration

“…This approach has led to detailed predictions of the intensity distributions of conically diffracted paraxial light beams [6][7][8]. These predictions have been shown to agree well with theory for the case of the conically diffracted Gaussian beam [9,10]. The propagation of paraxial light beams along the optic axes of successive biaxial crystals, known as cascade conical diffraction, has been receiving interest recently for the creation and annihilation of optical vortices [11], as a versatile beam shaping tool [12] and in connection with a novel type of laser based on conical diffraction [13].…”

“…Hence theory predicts that the FIP intensity distribution will consist of two concentric double ring patterns with dark ring radii of 0.9 and 0.16 mm. The same laser source was used in this experiment as in the case of equal length crystals but in this experiment a longer focal length lens was used to form the FIP on the CCD without an imaging lens (this point is discussed in [10]). The minimum waist of the Gaussian formed by the lens was 70 μm.…”