| Autor: |
Hyun-Yong Lee, Sung-June Cho, Gi-Yeon Nam, Wook-Hyun Lee, Takeshi Baba, Hisao Makino, Meoung-Whan Cho, Takafumi Yao |
| Zdroj: |
Journal of Applied Physics; 5/15/2005, Vol. 97 Issue 10, p103111-1-103111-4, 4p, 1 Diagram, 5 Graphs |
| Abstrakt: |
The Si/SiO2 one-dimensional photonic crystals of heterostructural multilayers with two periods, ΛA and ΛB, have great potential for multiple-wavelength-transmission filters. These structures were prepared by inserting N pairs of ΛB (as the defect region) in the middle of two sets of two pairs of ΛA, so that the structure becomes air→[(2.ΛA)→(N.ΛB)→(2.ΛA)]→(ubstrate. N means the number of ΛB pairs in the defect region. The complex refractive indices of Si and SiO2 are assumed to be 3.7+i0 and 1.5+i0 in the transfer matrix calculation. The number of transmission channels or defect branches m is given by 2N, that is, m=2N. For large N(>10), the photonic band gap exists in a normalized frequency range ω of 0.0846-0.3838, which corresponds to the wavelength range of 0.84-6.67 μm. The defect branches are placed on a branch band between two symmetric flat bands. For a filling factor η=0.406, a matching condition of optical length in two alternating layers, the branches at the center of the branch band are divided into a uniform frequency interval. In particular, we claim that the transmission-defect branches can be precisely tuned by controlling the incident angles without external applied bias. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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