Abstract

Guided longitudinal-acoustic modes, which give rise to Brillouin gain, are theoretically clarified for a single-mode fiber with a GeO₂-doped core and pure-silica cladding. Longitudinal-acoustic L_0m modes are found from the theoretical analysis to interact with the electromagnetic field of the HE₁₁ mode. Brillouin-gain spectra are measured for clarifying the theory. A few gain peaks in the Brillouin-gain spectra are successfully explained by taking account of the phase-velocity characteristics of the L₀₁, L₀₂ and L₀₃ modes guided in the GeO₂-doped core region. Furthermore, Brillouin frequency shifts per unit dopant concentration for GeO₂ and F are experimentally obtained to confirm the dispersion characteristics of the guided acoustic modes. The evaluated frequency shifts per unit dopant concentration are 107 and 356 MHz/mol% for GeO₂ and F, respectively, at a wavelength of 1550 nm.

© 1989 Optical Society of America

Identification of longitudinal acoustic modes guided in the core region of a single-mode optical fiber by Brillouin gain spectra measurements

Nori Shibata, Yuji Azuma, Tsuneo Horiguchi, and Mitsuhiro Tateda
Opt. Lett. 13(7) 595-597 (1988)

Brillouin-gain spectra for single-mode fibers having pure-silica, GeO₂-doped, and P₂O₅-doped cores

Nori Shibata, Robert G. Waarts, and Ralf P. Braun
Opt. Lett. 12(4) 269-271 (1987)

Brillouin frequency shifts in silica optical fiber with the double cladding structure

J. W. Yu, Y. Park, K. Oh, and I. B. Kwon
Opt. Express 10(19) 996-1002 (2002)

Acoustic modal analysis and control in w-shaped triple-layer optical fibers with highly-germanium-doped core and F-doped inner cladding

Weiwen Zou, Zuyuan He, and Kazuo Hotate
Opt. Express 16(14) 10006-10017 (2008)

A quasi-mode interpretation of acoustic radiation modes for analyzing Brillouin gain spectra of acoustically antiguiding optical fibers

Kyoungyoon Park and Yoonchan Jeong
Opt. Express 22(7) 7932-7946 (2014)