Bessel beam

About: Bessel beam is a research topic. Over the lifetime, 1946 publications have been published within this topic receiving 42264 citations.

Invited Article: Filamentary deposition of laser energy in glasses with Bessel beams

Abstract: We investigate the nonlinear absorption of laser energy in the bulk of transparent dielectrics for femtosecond and picosecond laser pulses focused by a conical lens. We highlight the influence of the pulse duration, laser pulse energy, and cone angle on laser energy absorption in transparent dielectrics. We provide a semi-analytical model allowing the calculation of maps for the density of nonlinear absorption of energy in BK7 and in SiO2 as a function of the pulse duration and peak fluence in the focal region. The comparison of the density of nonlinear absorption of energy with the available energy density determines optimal pulse durations and Bessel beam cone angles compatible with uniform laser energy deposition in the Bessel zone. The results reproduce quantitatively the transmission measurements for experiments in BK7 with picosecond pulses and suggest that the loss of propagation invariance and uniform laser energy deposition is responsible for a previously reported transition between different types of damage morphology in SiO2 [M. K. Bhuyan et al., Appl. Phys. Lett. 104, 021107 (2014)].

Analytical expressions for the longitudinal evolution of nondiffracting pulses truncated by finite apertures

Abstract: Starting from some general and plausible assumptions based on geometrical optics and on a common feature of the truncated Bessel beams, a heuristic derivation is presented of very simple analytical expressions capable of describing the longitudinal (on-axis) evolution of axially symmetric nondiffracting pulses truncated by finite apertures. The analytical formulation is applied to several situations involving subluminal, luminal, or superluminal localized pulses, and the results are compared with those obtained by numerical simulations of the Rayleigh-Sommerfeld diffraction integrals. The results are in excellent agreement. The present approach can be rather useful, because it yields, in general, closed-form expressions, avoiding the need for time-consuming numerical simulations, and also because such expressions provide a powerful tool for exploring several important properties of the truncated localized pulses, such as their depth of fields, the longitudinal pulse behavior, and the decaying rates.

Pulsed Bessel beam-induced microchannels on a diamond surface for versatile microfluidic and sensing applications

Abstract: We present a laser machining method based on the use of pulsed Bessel beams to create, by single pass transverse writing, three-dimensional trench-like microstructures on a synthetic monocrystalline diamond substrate By tuning the laser pulse energy and the writing speed, it is possible to control the features of the surface trenches obtained and to optimize the resulting high aspect-ratio and low roughness microstructures This work confirms the potentialities of quasi-stationary beams in ultra-fast laser inscription technology In particular the presented results show the possibility to fabricate deep and precise microfluidic channels on biocompatible diamond substrates, offering a great potential for biomedical sensing applications

Theory of self-phase-matching

Abstract: A theory of the recently discussed and demonstrated novel phenomenon of self-phase-matching [B. Glushko, B. Kryzhanovsky, and D. Sarkisyan, Phys. Rev. Lett. 71, 243 (1993)] is given by representing the conical beam, produced in the experiments, by a Bessel beam and as a superposition of Bessel beams. The predictions of the theory with the superposition of Bessel beams are in conformity with the observed behavior.