First-principles simulation of the optical response of bulk and thin-film α-quartz irradiated with an ultrashort intense laser pulse

Journal Article · Fri Feb 07 00:00:00 EST 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4864662· OSTI ID:22278094

Lee, Kyung-Min ^[1]; Min Kim, Chul; Sato, Shunsuke A. ^[2]; Otobe, Tomohito ^[3]; Shinohara, Yasushi ^[2]; Yabana, Kazuhiro ^[2]

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1. Advanced Photonics Research Institute, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)
2. Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba 305-8571 (Japan)
3. Kansai Photon Science Institute, Japan Atomic Energy Agency, Kizugawa, Kyoto 619-0215 (Japan)

A computational method based on a first-principles multiscale simulation has been used for calculating the optical response and the ablation threshold of an optical material irradiated with an ultrashort intense laser pulse. The method employs Maxwell's equations to describe laser pulse propagation and time-dependent density functional theory to describe the generation of conduction band electrons in an optical medium. Optical properties, such as reflectance and absorption, were investigated for laser intensities in the range 10{sup 10} W/cm{sup 2} to 2 × 10{sup 15} W/cm{sup 2} based on the theory of generation and spatial distribution of the conduction band electrons. The method was applied to investigate the changes in the optical reflectance of α-quartz bulk, half-wavelength thin-film, and quarter-wavelength thin-film and to estimate their ablation thresholds. Despite the adiabatic local density approximation used in calculating the exchange–correlation potential, the reflectance and the ablation threshold obtained from our method agree well with the previous theoretical and experimental results. The method can be applied to estimate the ablation thresholds for optical materials, in general. The ablation threshold data can be used to design ultra-broadband high-damage-threshold coating structures.

• OSTI ID: 22278094
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABLATION
APPROXIMATIONS
COMPUTERIZED SIMULATION
DENSITY FUNCTIONAL METHOD
ELECTRONIC STRUCTURE
ELECTRONS
MAXWELL EQUATIONS
OPACITY
PULSED IRRADIATION
QUARTZ
REFLECTIVITY
SPATIAL DISTRIBUTION
SPECTRAL REFLECTANCE
THIN FILMS
TIME DEPENDENCE