Ultrafast solid-liquid-vapor phase change of a thin gold film irradiated by femtosecond laser pulses and pulse trains

Melting, vaporization, and resolidification in a gold thin film subject to multiple femtosecond laser pulses are numerically studied in the framework of the two-temperature model. The solid-liquid phase change is modeled using a kinetics controlled model that allows the interfacial temperature to deviate from the melting point. The kinetics controlled model also allows superheating in the solid phase during melting and undercooling in the liquid phase during resolidification. Superheating of the liquid phase caused by nonequilibrium evaporation of the liquid phase is modeled by adopting the wave hypothesis, instead of the Clausius–Clapeyron equation. The melting depth, ablation depth, and maximum temperature in both the liquid and solid are investigated and the result is compared with that from the Clausius–Clapeyron equation based vaporization model. The vaporization wave model predicts a much higher vaporization speed, which leads to a deeper ablation depth. The relationship between laser processing parameters, including pulse separation time and pulse number, and the phase change effect are also studied. It is found that a longer separation time and larger pulse number will cause lower maximum temperature within the gold film and lower depths of melting and ablation.

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Ultrafast solid–liquid–vapor phase change of a gold film induced by pico- to femtosecond lasers

Applied Physics A ◽

10.1007/s00339-009-5156-8 ◽

2009 ◽

Vol 95 (3) ◽

pp. 643-653 ◽

Cited By ~ 24

Author(s):

Jing Huang ◽

Yuwen Zhang ◽

J. K. Chen

Keyword(s):

Phase Change ◽

Vapor Phase ◽

Gold Film ◽

Femtosecond Lasers ◽

Solid Liquid ◽

Liquid Vapor

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Melting, Vaporization and Resolidification in a Thin Gold Film Irradiated by Multiple Femtosecond Laser Pulses

Volume 1: Heat Transfer in Energy Systems; Theory and Fundamental Research; Aerospace Heat Transfer; Gas Turbine Heat Transfer; Transport Phenomena in Materials Processing and Manufacturing; Heat and ◽

10.1115/ht2012-58038 ◽

2012 ◽

Author(s):

Yijin Mao ◽

Yuwen Zhang ◽

J. K. Chen

Keyword(s):

Femtosecond Laser ◽

Gold Film ◽

Laser Pulses ◽

Femtosecond Laser Pulses ◽

Thin Gold Film

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Color Switching with Enhanced Optical Contrast in Ultrathin Phase-Change Materials and Semiconductors Induced by Femtosecond Laser Pulses

ACS Photonics ◽

10.1021/ph500402r ◽

2015 ◽

Vol 2 (2) ◽

pp. 178-182 ◽

Cited By ~ 45

Author(s):

Franziska F. Schlich ◽

Peter Zalden ◽

Aaron M. Lindenberg ◽

Ralph Spolenak

Keyword(s):

Femtosecond Laser ◽

Phase Change ◽

Phase Change Materials ◽

Laser Pulses ◽

Femtosecond Laser Pulses ◽

Optical Contrast ◽

Color Switching

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Effect of Energy Deposition Modes on Ultrafast Solid-Liquid-Vapor Phase Change of a Thin Gold Film Irradiated by a Femtosecond Laser

2010 14th International Heat Transfer Conference, Volume 6 ◽

10.1115/ihtc14-23050 ◽

2010 ◽

Author(s):

Jing Huang ◽

Yuwen Zhang ◽

J. K. Chen ◽

Mo Yang

Keyword(s):

Energy Balance ◽

Gold Film ◽

Pulse Number ◽

Thin Gold Film ◽

Solidification Temperature ◽

Vaporization Process ◽

Solid Liquid ◽

Two Temperature ◽

Temperature Melting ◽

Liquid Vapor

Effects of different parameters on the melting, vaporization and resolidification processes of thin gold film irradiated by a femtosecond pulse laser are systematically studied. The classical two-temperature model was adopted to depict the non-equilibrium heat transfer in electrons and lattice. The melting and resolidification processes, which was characterized by the solid-liquid interfacial velocity, as well as elevated melting temperature and depressed solidification temperature, was obtained by considering the interfacial energy balance and nucleation dynamics. Vaporization process which leads to ablation was described by tracking the location of liquid-vapor interface with an iterative procedure based on energy balance and gas kinetics law. The parameters in discussion include film thickness, laser fluence, pulse duration, pulse number, repetition rate, pulse train number, etc. Their effects on the maximum lattice temperature, melting depth and ablation depth are discussed based on the simulation results.

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