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Title: Hollow core waveguide as mid-infrared laser modal beam filter

Abstract

A novel method for mid-IR laser beam mode cleaning employing hollow core waveguide as a modal filter element is reported. The influence of the input laser beam quality on fiber optical losses and output beam profile using a hollow core waveguide with 200 μm-bore size was investigated. Our results demonstrate that even when using a laser with a poor spatial profile, there will exist a minimum fiber length that allows transmission of only the Gaussian-like fundamental waveguide mode from the fiber, filtering out all the higher order modes. This essentially single mode output is preserved also when the waveguide is bent to a radius of curvature of 7.5 cm, which demonstrates that laser mode filtering can be realized even if a curved light path is required.

Authors:
; ;  [1];  [1];  [2];  [3];  [4]
  1. Dipartimento Interateneo di Fisica, Università e Politecnico di Bari, CNR-IFN UOS BARI, Via Amendola 173, 70126 Bari (Italy)
  2. (United States)
  3. Opto-Knowledge Systems, Inc. (OKSI), 19805 Hamilton Ave., Torrance, California 90502-1341 (United States)
  4. Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005 (United States)
Publication Date:
OSTI Identifier:
22489484
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 118; Journal Issue: 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BEAMS; FIBERS; FILTERS; LASERS; LENGTH; LOSSES; TRANSMISSION; WAVEGUIDES

Citation Formats

Patimisco, P., Giglio, M., Spagnolo, V., Sampaolo, A., Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, Kriesel, J. M., and Tittel, F. K.. Hollow core waveguide as mid-infrared laser modal beam filter. United States: N. p., 2015. Web. doi:10.1063/1.4930893.
Patimisco, P., Giglio, M., Spagnolo, V., Sampaolo, A., Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, Kriesel, J. M., & Tittel, F. K.. Hollow core waveguide as mid-infrared laser modal beam filter. United States. doi:10.1063/1.4930893.
Patimisco, P., Giglio, M., Spagnolo, V., Sampaolo, A., Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, Kriesel, J. M., and Tittel, F. K.. 2015. "Hollow core waveguide as mid-infrared laser modal beam filter". United States. doi:10.1063/1.4930893.
@article{osti_22489484,
title = {Hollow core waveguide as mid-infrared laser modal beam filter},
author = {Patimisco, P. and Giglio, M. and Spagnolo, V. and Sampaolo, A. and Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005 and Kriesel, J. M. and Tittel, F. K.},
abstractNote = {A novel method for mid-IR laser beam mode cleaning employing hollow core waveguide as a modal filter element is reported. The influence of the input laser beam quality on fiber optical losses and output beam profile using a hollow core waveguide with 200 μm-bore size was investigated. Our results demonstrate that even when using a laser with a poor spatial profile, there will exist a minimum fiber length that allows transmission of only the Gaussian-like fundamental waveguide mode from the fiber, filtering out all the higher order modes. This essentially single mode output is preserved also when the waveguide is bent to a radius of curvature of 7.5 cm, which demonstrates that laser mode filtering can be realized even if a curved light path is required.},
doi = {10.1063/1.4930893},
journal = {Journal of Applied Physics},
number = 11,
volume = 118,
place = {United States},
year = 2015,
month = 9
}
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