Femtosecond laser absorption in fused silica: Numerical and experimental investigation

Wu, Alexander Q.; Chowdhury, Ihtesham H.; Xu, Xianfan

doi:10.1103/physrevb.72.085128

Cited by 126 publications

(107 citation statements)

References 21 publications

Supporting

Mentioning

100

Contrasting

Unclassified

Order By: Relevance

“…[10][11][12][13] and Refs. [14][15][16][17][18]. The necessity of photoionization, however, as at least a prerequisite to permanent LID stands in good agreement with nearly all models.…”

Section: Introductionsupporting

confidence: 61%

Frequency dependence in the initiation of ultrafast laser-induced damage

Gulley

2010

SPIE Proceedings

View full text Add to dashboard Cite

Numerous studies have investigated the role of photoionization in ultrafast laser-induced damage of bulk dielectrics. This study examines the role of spectral width and instantaneous laser frequency in laser-induced damage using a frequency dependent multiphoton ionization model and numerical simulation of an 800 nm laser pulse propagating through fused silica. When the individual photon wavelengths are greater than 827 nm, an additional photon is required for photoionization, reducing the probability of the event by many orders of magnitude. Simulation results suggest that this frequency dependence may significantly affect the processes of laser-induced damage and filamentation.

show abstract

“…[10][11][12][13] and Refs. [14][15][16][17][18]. The necessity of photoionization, however, as at least a prerequisite to permanent LID stands in good agreement with nearly all models.…”

Section: Introductionsupporting

confidence: 61%

Frequency dependence in the initiation of ultrafast laser-induced damage

Gulley

2010

SPIE Proceedings

View full text Add to dashboard Cite

show abstract

“…In both equations the photoionization rate W PI is calculated using the Keldysh model [32] with a reduced electron-hole mass of half the electron rest mass and the one-photon absorption cross section σ as derived from the Drude model [30,33]. In solving the multirate equation we also assume an exponential loss of free carriers from the conduction band with a recombination time of 150 fs [19,34]. The variables and parameters in Eq.…”

Section: Simulationmentioning

confidence: 99%

Interaction of ultrashort-laser pulses with induced undercritical plasmas in fused silica

et al. 2012

View full text Add to dashboard Cite

R. 2012. Interaction of ultrashort-laser pulses with induced undercritical plasmas in fused silica. Phys Rev A, 85(1):013808.PHYSICAL REVIEW A 85, 013808 (2012) Interaction of ultrashort-laser pulses with induced undercritical plasmas in fused silica Ultrafast light-material interactions near the damage threshold are often studied using postmortem analysis of damaged dielectric materials. Corresponding simulations of ultrashort pulse propagation through the material are frequently used to gain additional insight into the processes leading to such damage. However, comparison between such experimental and numerical results is often qualitative, and pulses near to but not exceeding the damage threshold leave no permanent changes in the material for postmortem analysis. In this article, a series of experiments is presented that measures the near-and far-field properties of a 140-fs laser pulse after propagation through a fused silica sample in which a noncritical electron plasma was generated. Concurrently, results from simulations in which the laser pulse was numerically constructed according to the nearfield beam profile and frequency resolved optical gating (FROG) trace are presented. It is found that to extract a quantitative comparison of such data, cylindrical symmetry of the laser pulse in simulations should be abandoned in favor of a fully 3 + 1D Cartesian representation. Further comparison of experimental and calculated damage thresholds shows that time-corrective effects predicted by the Drude model play a critical role in the physics of both pulse evolution and plasma formation. The influence of resulting spatiotemporal dependences of the pulse in far-field measurements leads to unretrievable FROG traces. However, it is shown through both simulation and experiment that the use of an appropriate beam aperture will eliminate this effect when measuring the temporal pulse amplitude.

show abstract

“…Correct and practical modeling of impact ionization (or avalanching) during LID on the femtosecond time scale is still an open question in the literature. [10][11][12][13][14][15][16][17][18] However, the necessity of photoionization as a prerequisite to permanent LID stands in good agreement with nearly all models. Therefore, it is reasonable to assume that errors of many orders of magnitude in calculations of the photoionization rate threaten the validity numerical LID predictions.…”

Section: Introductionmentioning

confidence: 82%

“…For the remainder of this work, the Keldysh photoionization rate for solids is used because in numerous studies it has provided good agreement with experiments of ultrashort laser pulse propagation in fused silica, 6,11,18,[22][23][24][25][26][27][28] and fused silica will be the material referenced in this work. The photoionization formula developed by Keldysh for solids is 19 W PI ðjξj; ω; U; mÞ ¼ 2ω 9π…”

Section: Keldysh Model Of Photoionizationmentioning

confidence: 99%

Ultrafast laser-induced damage and the influence of spectral effects

Gulley

2012

Opt. Eng

View full text Add to dashboard Cite

Abstract. Numerous studies have investigated the prerequisite role of photoionization in ultrafast laser-induced damage (LID) of bulk dielectrics. This study examines the role of spectral width and instantaneous laser frequency in LID using a frequency dependent multiphoton ionization (MPI) model and numerical simulation of initially 800 nm laser pulses propagating through fused silica. Assuming a band gap of 9 eV, MPI by an 800 nm field is a six-photon process, but when the instantaneous wavelength is greater than 827 nm an additional photon is required for photoionization, reducing the probability of the event by many orders of magnitude. Simulation results suggest that this frequency dependence can significantly impact the onset of LID and ultrashort pulse filamentation in solids.

show abstract

Femtosecond laser absorption in fused silica: Numerical and experimental investigation

Cited by 126 publications

References 21 publications

Frequency dependence in the initiation of ultrafast laser-induced damage

Frequency dependence in the initiation of ultrafast laser-induced damage

Interaction of ultrashort-laser pulses with induced undercritical plasmas in fused silica

Ultrafast laser-induced damage and the influence of spectral effects

Contact Info

Product

Resources

About