Open AccessTheoretical analysis of second-harmonic conversion efficiency in negative-index materials
Author(s) -
Zhou Cheng,
Yanxia Gao,
Pei-ji Wang,
Zhiyuan Zhong,
Ping Li
Publication year - 2009
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.58.914
Subject(s) - energy conversion efficiency , absorption efficiency , absorption (acoustics) , phase (matter) , basis (linear algebra) , harmonic , materials science , mathematics , physics , optics , thermodynamics , acoustics , zoology , quantum mechanics , geometry , biology
For negative-index materials(NIM) of second-harmonic wave(SHW) and positive-index materials of fundamental frequency wave(FFW)the equations of the coupled wave was deducedtaking account of absorption coefficientwalk-off effectphase mismatching capacity and the approximation of slow-varying amplitudes of the plane wave. On the basis of the equationsa formulation of SHW conversion efficiency was obtained in condition of small signal approximation for FFW. Through numerical simulation, the effects of phase mismatching capacitywalk-off angle and absorption coefficient of SHW on the conversion efficiency of SHW were scrutinized respectively. The maximum conversion efficiency of SHW was realized via increasing the length of NIMthat isthere exists an optimum length of NIM; however, the conversion efficiency of SHW shows an evidencet periodic evolution and the maximum conversion efficiency always diminishes. The conversion efficiency decreases with the increases of the phase mismatching capacity and the absorption coefficient. The influence of walk-off effect is not evident so that it may be neglected with respect to the conversion efficiency of SHW. This study provides a basis for investigating nonlinear theory of negative-index materials.