Jung Yongduck, Kim Youngmin, Burt Daniel, Joo Hyo-Jun, Kang Dong-Ho, Luo Manlin, Chen Melvina, Zhang Lin, Tan Chuan Seng, Nam Donguk
Opt Express. 2021 May 10;29(10):14174-14181. doi: 10.1364/OE.417330.
The creation of CMOS compatible light sources is an important step for the realization of electronic-photonic integrated circuits. An efficient CMOS-compatible light source is considered the final missing component towards achieving this goal. In this work, we present a novel crossbeam structure with an embedded optical cavity that allows both a relatively high and fairly uniform biaxial strain of ∼0.9% in addition to a high-quality factor of >4,000 simultaneously. The induced biaxial strain in the crossbeam structure can be conveniently tuned by varying geometrical factors that can be defined by conventional lithography. Comprehensive photoluminescence measurements and analyses confirmed that optical gain can be significantly improved via the combined effect of low temperature and high strain, which is supported by a three-fold reduction of the full width at half maximum of a cavity resonance at ∼1,940 nm. Our demonstration opens up the possibility of further improving the performance of germanium lasers by harnessing geometrically amplified biaxial strain.
创建与CMOS兼容的光源是实现电子 - 光子集成电路的重要一步。高效的CMOS兼容光源被认为是实现这一目标的最后一个缺失组件。在这项工作中，我们提出了一种具有嵌入式光学腔的新型横梁结构，该结构除了同时具有大于4000的高品质因数外，还允许约0.9%的相对较高且相当均匀的双轴应变。通过改变可由传统光刻定义的几何因素，可以方便地调节横梁结构中感应的双轴应变。全面的光致发光测量和分析证实，通过低温和高应变的联合效应，可以显著提高光学增益，这在约1940 nm处腔共振的半高宽降低三倍中得到了支持。我们的演示为通过利用几何放大的双轴应变进一步提高锗激光器的性能开辟了可能性。
