2004 Fiscal Year Final Research Report Summary
Accurate Measurement of Second-Order Nonlinear-Optical Coefficients of Stoichiometric LiNbO3 and LiTaO3
| Project/Area Number |
15560035
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Applied optics/Quantum optical engineering
|
|---|
| Research Institution | CHUO UNIVERSITY (2004)
Meiji University (2003) |
|---|
Principal Investigator |
SHOJI Ichiro Chuo University, Faculty of Science and Engineering, Assistant Professor, 理工学部, 専任講師 (90272385)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ITO Ryoichi University of Tokyo, Emeritus Professor, Meiji University Assistant Professor, 理工学部, 兼任講師・東京大学名誉教授 (40133102)
|
|---|
| Project Period (FY) |
2003 – 2004
|
| Keywords | stoichiometric LiNbO_3 / stoichiometric-composition LiNbO3 / stoichiometric MgO:LiNbO3 / stoichiometric-composition MgO:LINbO3 / nonlinear-optical coefficient / Maker fringe / wedge method |
|---|
| Research Abstract |
We have measured second-order nonlinear-optical coefficients of stoichiometric LiNbO_3, the high-quality crystals of which have been recently developed.
The measurement was performed at the fundamental wavelengths of 1.06 and 1.31μm. Undoped and MgO-doped crystals were grown by Oxide company and Hitachi Metals company. They were cut and polished to the wedge samples with the wedge angle of 〜0.15 degree, and the fundamental light was normally focused onto the sample. The dependence of the generated second-harmonic power on the sample thickness, or Maker fringe, was measured. We fully took account of the multiple-reflection effect in the nearly plane-parallel-plate samples.
The accurate refractive indices which are essential for analyzing the data are not available for stoichiometric LiNbO_3. If the wedge angle is known, the refractive indices can be obtained by the measurement of the Maker-fringe period. Because it is difficult to directly measure the wedge angle within 10^<-3> accuracy, we estimated the wedge angle and the refractive indices by measurement of the period of interference caused by the multiple reflection in the sample, and of dependence of the transmittance on the sample displacement in the cross-Nicole configuration, both at the fundamental and the second-harmonic wavelengths. This enabled us to determine the nonlinear-optical coefficients with the accuracy of better than 5%, and we found that the nonlinear-optical coefficients of stoichiometric LiNbO_3 and MgO:LiNbO_3 are same with that of congruent ones within the measurement accuracy.
|
