New method to determine the refractive index and the absorption coefficient of organic nonlinear crystals in the ultra-wideband THz region

被引：34

作者：

Ohno, Seigo ^{[1
]}

Miyamoto, Katsuhiko ^{[1
]}

Minamide, Hiroaki ^{[1
]}

Ito, Hiromasa ^{[1
]}

机构：

[1] RIKEN ASI, Aoba Ku, Sendai, Miyagi 9800845, Japan

来源：

OPTICS EXPRESS | 2010年 / 18卷 / 16期

基金：

日本科学技术振兴机构; 日本学术振兴会;

关键词：

TERAHERTZ-WAVE GENERATION; DAST CRYSTALS; TOSYLATE;

D O I：

10.1364/OE.18.017306

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

A method for simultaneously measuring the refractive index and absorption coefficient of nonlinear optical crystals in the ultra-wideband terahertz (THz) region is described. This method is based on the analysis of a collinear difference frequency generation (DFG) process using a tunable, dual-wavelength, optical parametric oscillator. The refractive index and the absorption coefficient in the organic nonlinear crystal DAST were experimentally determined in the frequency range 2.5-26.2 THz by measuring the THz-wave output using DFG. The resultant refractive index in the x-direction was similar to 2.3, while the absorption spectrum was in good agreement with FT-IR measurements. The output of the DAST-DFG THz-wave source was optimized to the phase-matching condition using the measured refractive index spectrum in THz region, which resulted in an improvement in the output power of up to a factor of nine. (C) 2010 Optical Society of America

引用

页码：17306 / 17312

页数：7

共 15 条

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