Dependence of the XeCl laser cut rate of plaque on the degree of calcification, laser fluence, and optical pulse duration

1990 ◽  
Vol 10 (5) ◽  
pp. 414-419 ◽  
Author(s):  
Rod S. Taylor ◽  
Lyall A. J. Higginson ◽  
Kurt E. Leopold
Keyword(s):  
Pulse Duration ◽  
Laser Fluence ◽  
Optical Pulse ◽  
Xecl Laser

Effect of optical pulse duration on the XeCl laser ablation of polymers and biological tissue

1987 ◽  
Vol 50 (25) ◽  
pp. 1779-1781 ◽  
Author(s):  
R. S. Taylor ◽  
D. L. Singleton ◽  
G. Paraskevopoulos
Keyword(s):  
Laser Ablation ◽  
Pulse Duration ◽  
Biological Tissue ◽  
Optical Pulse ◽  
Xecl Laser

Modeling Electron-Phonon Nonequilibrium in Gold Films Using Boltzmann Transport Model

2009 ◽  
Vol 131 (8) ◽  
Author(s):  
Arvind Pattamatta ◽  
Cyrus K. Madnia
Keyword(s):  
Film Thickness ◽  
Pulse Duration ◽  
Laser Fluence ◽  
Laser Heating ◽  
Gold Film ◽  
Transport Model ◽  
Melting Time ◽  
Gold Films ◽  
Boltzmann Transport ◽  
Energy Carriers

Ultrashort-pulsed laser irradiation on metals creates a thermal nonequilibrium between electrons and the phonons. Previous computational studies used the two-temperature model and its variants to model this nonequilibrium. However, when the laser pulse duration is smaller than the relaxation time of the energy carriers or when the carriers’ mean free path is larger than the material dimension, these macroscopic models fail to capture the physics accurately. In this paper, the nonequilibrium between energy carriers is modeled via a numerical solution of the Boltzmann transport model (BTM) for electrons and phonons, which is applicable over a wide range of lengths and time scales. The BTM is solved using the discontinuous Galerkin finite element method for spatial discretization and the three-step Runge–Kutta temporal discretization. Temperature dependent electron-phonon coupling factor and electron heat capacity are used due to the strong electron-phonon nonequilibrium considered in this study. The results from the proposed model are compared with existing experimental studies on laser heating of macroscale materials. The model is then used to study laser heating of gold films, by varying parameters such as the film thickness, laser fluence, and pulse duration. It is found that the temporal evolution of electron and phonon temperatures in nanometer size gold films is very different from the macroscale films. For a given laser fluence and pulse duration, the peak electron temperature increases with a decrease in the thickness of the gold film. Both film thickness and laser fluence significantly affect the melting time. For a fluence of 1000 J/m2, and a pulse duration of 75 fs, gold films of thickness smaller than 100 nm melt before reaching electron-phonon equilibrium. However, for the film thickness of 2000 nm, even with the highest laser fluence examined, the electrons and phonons reach equilibrium and the gold film does not melt.

Pre‐preionization of a long optical pulse magnetic‐spiker sustainer XeCl laser

1994 ◽  
Vol 65 (12) ◽  
pp. 3621-3627 ◽  
Author(s):  
R. S. Taylor ◽  
K. E. Leopold
Keyword(s):  
Optical Pulse ◽  
Xecl Laser

Time-resolved measurements of emission and absorption in a long pulse duration XeCl* laser

1984 ◽  
Vol 45 (9) ◽  
pp. 1449-1456 ◽  
Author(s):  
D.C. Hogan ◽  
A.J. Kearsley ◽  
C.E. Webb ◽  
R. Bruzzese
Keyword(s):  
Pulse Duration ◽  
Xecl Laser ◽  
Time Resolved ◽  
Long Pulse ◽  
Time Resolved Measurements

Dependence of excimer laser ablation of the human artery wall on wavelength and optical pulse duration

1986 ◽  
Author(s):  
R. S. Taylor ◽  
D. L. Singleton ◽  
G. Paraskevopoulos ◽  
G. S. Jolly ◽  
E. Farrell ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Pulse Duration ◽  
Excimer Laser ◽  
Optical Pulse ◽  
Artery Wall ◽  
Human Artery ◽  
Excimer Laser Ablation

scholarly journals Laser-induced ablation of tantalum in a wide range of pulse durations

2020 ◽  
Vol 126 (9) ◽  
Author(s):  
Steffen Mittelmann ◽  
Jannis Oelmann ◽  
Sebastijan Brezinsek ◽  
Ding Wu ◽  
Hongbin Ding ◽  
...  
Keyword(s):  
Confocal Microscopy ◽  
Laser Pulse ◽  
Femtosecond Laser ◽  
Pulse Duration ◽  
Laser Fluence ◽  
Crater Depth ◽  
Nanosecond Laser ◽  
Threshold Fluence ◽  
Wide Range ◽  
Laser Systems

Abstract We present data and analysis of the laser-induced ablation of pure tantalum (Ta, $$Z=73$$ Z = 73 ). We have identified different physical regimes using a wide range of laser pulse durations. A comparison of the influence of strongly varying laser pulse parameters on high-Z materials is presented. The crater depth caused by three different laser systems of pulse duration $${\varDelta }\tau _1=5\,\mathrm {ns}$$ Δ τ 1 = 5 ns and wavelength $$\lambda _1=1064\,\mathrm {nm}$$ λ 1 = 1064 nm , $${\varDelta }\tau _2=35\,\mathrm {ps}$$ Δ τ 2 = 35 ps , $$\lambda _2=355\,\mathrm {nm}$$ λ 2 = 355 nm and $${\varDelta }\tau _3=8.5\,\mathrm {fs}$$ Δ τ 3 = 8.5 fs , $$\lambda _3=790\,\mathrm {nm}$$ λ 3 = 790 nm are analyzed via confocal microscopy as a function of laser fluence and intensity. The minimum laser fluence needed for ablation, called threshold fluence, decreases with shorter pulse duration from $$1.10\,\mathrm {J/cm}^2$$ 1.10 J / cm 2 for the nanosecond laser to $$0.17\,\mathrm {J/cm}^2$$ 0.17 J / cm 2 for the femtosecond laser.

Ultralong optical‐pulse corona preionized XeCl laser

1989 ◽  
Vol 65 (1) ◽  
pp. 22-29 ◽  
Author(s):  
Rod S. Taylor ◽  
Kurt E. Leopold
Keyword(s):  
Optical Pulse ◽  
Xecl Laser ◽  
Pulse Corona

scholarly journals Ultrafast dynamical process of Ge irradiated by the femtosecond laser pulses

2016 ◽  
Vol 4 ◽  
Author(s):  
Fangjian Zhang ◽  
Shuchang Li ◽  
Anmin Chen ◽  
Yuanfei Jiang ◽  
Suyu Li ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Pulse Duration ◽  
Laser Fluence ◽  
Carrier Density ◽  
Laser Intensity ◽  
Great Influence ◽  
Laser Pulses ◽  
Femtosecond Laser Pulses ◽  
Lattice Temperature ◽  
Dynamical Process

The ultrafast dynamic process in semiconductor Ge irradiated by the femtosecond laser pulses is numerically simulated on the basis of van Driel system. It is found that with the increase of depth, the carrier density and lattice temperature decrease, while the carrier temperature first increases and then drops. The laser fluence has a great influence on the ultrafast dynamical process in Ge. As the laser fluence remains a constant value, though the overall evolution of the carrier density and lattice temperature is almost independent of pulse duration and laser intensity, increasing the laser intensity will be more effective than increasing the pulse duration in the generation of carriers. Irradiating the Ge sample by the femtosecond double pulses, the ultrafast dynamical process of semiconductor can be affected by the temporal interval between the double pulses.

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