Theory of the quasi-steady-state self-focusing of partially coherent light pulses in nonlinear media

Abstract

The quasi-steady-state (QSS) self-focusing of partially coherent light pulses (PCLPs) in nonlinear media is studied. The analytical formulas of the QSS self-focusing of PCLPs in nonlinear media (e.g., the beam width, spatial coherence width, and focal length) are presented. The effect of spatial coherence on the focal length and focus moving is investigated in detail. In particular, it is found that a PCLP has more advantages to avoid the optical damage of materials than a fully coherent light pulse.

One-Step Femtosecond Laser Stealth Dicing of Quartz

“…Considering that the applied peak power ranged from 75 MW to 175 MW, the calculated self-focusing distance ranged between 0.31 μm and 0.47 μm. Correspondingly, the spot radius at such distance was determined according to [34]:…”

Generation of pulse trains with nonconventional temporal correlation properties

“…This is the complex degree of spectral coherence of a non-uniformly correlated pulse train [42]. The MCF of this pulse train is obtained on inserting from equation ( 21) into equation (20). Again the integral needs to be evaluated numerically.…”

“…In addition to spatially partially coherent fields, a large number of temporally partially coherent model pulse trains have been theoretically introduced [17][18][19][20], with several potential applications including temporal ghost imaging [21][22][23], inertial confinement fusion [24][25][26], telecommunication [27][28][29], and micro-machining [30,31], to name a few. Many of these statistically nonstationary fields have timedomain coherence properties that are quite analogous to the spatial coherence of the stationary beam fields.…”

Self-Focusing Property of Partially Coherent Beam With Non-Uniform Correlation Structure in Non-Linear Media

“…Mutual coherence function, i.e., W(r i , r j ) 〈E(r i )E p (r j )〉 (i, j 1, 2), is a common method to solve PCBs in propagation media [1,[31][32][33][34]. Equation 2 can be converted to [10,[12][13][14]…”

“…There are several approaches to describe the propagation of PCBs in a non-linear medium, for example, the coherent density approach [7], multimode decomposition [8], the geometric optics approach [9], and the mutual coherence function [1]. At present, the Gaussian-Schell source model (GSM) of a partially coherent beam propagating in a non-linear medium is frequently used [10][11][12][13][14]. With a spatially variant correlation function proposed by Gori et al [15], PCBs with a non-uniform correlation structure not only exhibit self-focusing and self-shifting properties [16][17][18][19] but also produce lower scintillation in turbulence [20,21] than that of GSM beams.…”