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Title: Self-organization of a periodic structure between amorphous and crystalline phases in a GeTe thin film induced by femtosecond laser pulse amorphization

Abstract

A self-organized fringe pattern in a single amorphous mark of a GeTe thin film was formed by multiple femtosecond pulse amorphization. Micro Raman measurement indicates that the fringe is a periodic alternation between crystalline and amorphous phases. The period of the fringe is smaller than the irradiation wavelength and the direction is parallel to the polarization direction. Snapshot observation revealed that the fringe pattern manifests itself via a complex but coherent process, which is attributed to crystallization properties unique to a nonthermally amorphized phase and the distinct optical contrast between crystalline and amorphous phases.

Authors:
; ; ; ;  [1]
  1. Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku, Yokohama, Kanagawa 223-8522 (Japan)
Publication Date:
OSTI Identifier:
22311132
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMORPHOUS STATE; CRYSTALLIZATION; GERMANIUM TELLURIDES; IRRADIATION; LASER RADIATION; PERIODICITY; POLARIZATION; PULSES; RAMAN EFFECT; THIN FILMS; WAVELENGTHS

Citation Formats

Katsumata, Y., Morita, T., Morimoto, Y., Shintani, T., and Saiki, T.. Self-organization of a periodic structure between amorphous and crystalline phases in a GeTe thin film induced by femtosecond laser pulse amorphization. United States: N. p., 2014. Web. doi:10.1063/1.4890862.
Katsumata, Y., Morita, T., Morimoto, Y., Shintani, T., & Saiki, T.. Self-organization of a periodic structure between amorphous and crystalline phases in a GeTe thin film induced by femtosecond laser pulse amorphization. United States. doi:10.1063/1.4890862.
Katsumata, Y., Morita, T., Morimoto, Y., Shintani, T., and Saiki, T.. 2014. "Self-organization of a periodic structure between amorphous and crystalline phases in a GeTe thin film induced by femtosecond laser pulse amorphization". United States. doi:10.1063/1.4890862.
@article{osti_22311132,
title = {Self-organization of a periodic structure between amorphous and crystalline phases in a GeTe thin film induced by femtosecond laser pulse amorphization},
author = {Katsumata, Y. and Morita, T. and Morimoto, Y. and Shintani, T. and Saiki, T.},
abstractNote = {A self-organized fringe pattern in a single amorphous mark of a GeTe thin film was formed by multiple femtosecond pulse amorphization. Micro Raman measurement indicates that the fringe is a periodic alternation between crystalline and amorphous phases. The period of the fringe is smaller than the irradiation wavelength and the direction is parallel to the polarization direction. Snapshot observation revealed that the fringe pattern manifests itself via a complex but coherent process, which is attributed to crystallization properties unique to a nonthermally amorphized phase and the distinct optical contrast between crystalline and amorphous phases.},
doi = {10.1063/1.4890862},
journal = {Applied Physics Letters},
number = 3,
volume = 105,
place = {United States},
year = 2014,
month = 7
}
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