Gai Xin, Luther-Davies Barry, White Thomas P
Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, ACT 2600, Australia.
Opt Express. 2012 Jul 2;20(14):15503-15. doi: 10.1364/OE.20.015503.
We have designed and fabricated a 2-D photonic crystal hetero-structure cavity in the chalcogenide glass Ge(11.5)As(24)Se(64.5) that is fully embedded in a cladding with refractive index of 1.44. The low index contrast of this structure (≈1.21) means that high-Q resonances cannot be obtained using standard hetero-structure cavity designs based on W1 waveguides. We show that reducing the waveguide width can substantially improve light confinement, leading to high-Q resonances in a hetero-structure cavity. Numerical simulations indicate intrinsic Q(v) > 10(7) are possible with this approach. Experimentally, an optical cavity with a high intrinsic Q(v)>7.6 x 10(5) was achieved in a structure with a theoretical Q(v) = 1.7 x 10(6).
我们在硫族化物玻璃Ge(11.5)As(24)Se(64.5)中设计并制造了一种二维光子晶体异质结构腔，该腔完全嵌入在折射率为1.44的包层中。这种结构的低折射率对比度（≈1.21）意味着，基于W1波导的标准异质结构腔设计无法获得高Q共振。我们表明，减小波导宽度可显著改善光限制，从而在异质结构腔中实现高Q共振。数值模拟表明，采用这种方法可能实现本征Q(v)>10⁷。实验上，在理论Q(v)=1.7 x 10⁶的结构中实现了本征Q(v)>7.6 x 10⁵的光学腔。
