SBIR Phase I: Low Cost High Brightness Photonic Crystal Lasers with Integrated Non-Linear Crystals

这个小型企业创新研究(SBIR)第一阶段项目的目标是开发一种工作在900至1070 nm波长范围内的高度相干表面发射光子晶体(SEPC)半导体激光器。高亮度激光器需要高效泵浦非线性晶体，以获得倍频绿光(~532 nm)和倍频蓝光(~470 nm)。最初的样机将工作在976 nm的波长附近，产生488 nm的倍频输出，作为Ar离子激光器的替代品。为了实现高亮度，SEPC激光器的概念包括在外延结构中包括一个反射堆栈，以最大限度地减少由于SE光子晶体的双向出耦合而导致的朝向外延(p侧)金属接触的光损失。倍频SEPC激光器的广泛应用包括投影显示、生物仪器、半导体晶片检测和化学传感。此外，SEPC二极管激光器将作为光纤激光器的直接替代品得到应用。此外，SEPC激光器阵列将在包括机械加工、材料加工和医疗应用在内的市场中用作具有高光束质量的高功率激光光源。表面发射使完整的晶片加工和测试成为可能，由于硅IC行业的规模经济，这些优势允许提高可靠性并显著降低成本。表面发射还消除了对刻面涂层的需要，防止了灾难性的光学损害(COD)以及刻面退化。因此，这种SEPC器件具有极低的成本和接近50%的电光效率的潜力。与用于泵浦应用的传统广域半导体激光器相比，具有高度相干、高亮度、单瓣远场的单频运行提供了额外的有效效率。此外，SEPC激光器的输出孔径大小可以设计为在没有外部光学元件的情况下产生圆形输出光束，从而进一步降低激光组件的成本。

This Small Business Innovation Research (SBIR) Phase I project goal is to develop a highly coherent surface-emitting photonic crystal (SEPC) semiconductor laser operating in the 900 to 1070 nm wavelength range. High brightness lasers are required to efficiently pump non-linear crystals to obtain frequency doubled green (~532 nm) and blue (~470 nm) light. Initial prototypes will operate around wavelength of 976 nm to produce frequency doubled output at 488 nm as replacement for argon-ion lasers. To achieve high brightness the SEPC laser concept includes within the epitaxial structure a reflecting stack to minimize loss of light towards the epitaxial (p-side) metal contact caused by the bi-directional outcoupling of the SE photonic crystal.A broad set of applications for the frequency-doubled SEPC lasers include projection display, bioinstrumentation, semiconductor wafer inspection and chemical sensing. In addition, SEPC diode lasers will find application as direct replacement for fiber lasers. Furthermore, arrays of SEPC lasers will be used as high power laser sources with high beam quality in markets that include machining, material processing, and medical applications. Surface-emission makes possible complete wafer processing and testing, advantages that permitted improved reliability and significant reductions in cost due to the economy of scale for the silicon IC industry. Surface emission also eliminates the need for facet coating and prevents catastrophic optical damage (COD) as well as facet degradation. As a result, this SEPC device has potential for extremely low cost and electrical to optical efficiencies approaching 50%. The single frequency operation with a highly coherent, high brightness, single-lobe far-field provides an additional effective efficiency compared to conventional broad area diode lasers for pump applications. In addition, the output aperture size of the SEPC laser can be engineered to produce circular output beam without external optics further reducing the cost of the laser package.