Chalcogenide Photonic Technologies

硫族化合物是以硫、硒和/或碲的金属合金为基础的材料。虽然在20世纪50年代才首次形成玻璃，但它们首先出现在新一代CD和DVD中，因为它们能够形成玻璃和晶体结构，从而可以存储信息。这种光存储是基于激光加热硫系物质并将其从晶体结构转变为玻璃结构时光学性质的变化。这种相变效应也正在积极研究电子存储器，最终目标是取代目前的记忆棒技术。硫族化合物在这里提供了更高的读写速率，更小的存储单元大小，并随着时间的推移提高了稳定性。在这项工作中，我们的目标是通过利用和增强我们在沉积硫族化物薄膜和随后在这些薄膜中形成光导方面的专业知识，进一步开发硫族化物的光电应用。光在波导中的限制将增强导光功率，并可能导致基于上述相变的器件。然而，硫属化合物对光的响应速度更快、更强，这可以通过波导结构设计得非常有效，使我们能够开发超高速光开关元件、在光波长之间转换的设备（改变“颜色”）和量子光源以“怪异连接”的纠缠对发射光子。通过在波导中掺杂过渡金属，我们希望制造出具有大量新波长的激光器，特别是在红外区域。硫系玻璃在更长的波长下具有比传统玻璃更高的透射率，将激光应用扩展到用于航空航天，化学传感和专业医疗传感器的眼睛安全测距仪。

Chalcogenides are materials based on metallic alloys of sulphur, selenium and/or tellurium. Although only formed into glasses for the first time in the 1950's, they emerged first in a new generation of CD's and DVD's where their ability to be formed into glass and crystalline structures allow information to be stored. This optical storage is based on changes of optical properties when a laser heats the chalcogenide material and converts it from crystalline to glass structure. This phase change effect is also being actively investigated for electronic memories ultimately aiming to replace present memory stick technology. Chalcogenides here offer vastly higher read and write rates, smaller memory cell size and improved stability over time.In the proposed work, we are aiming to develop further optoelectronic applications of chalcogenides by exploiting and enhancing our expertise in depositing thin films of chalcogenide and subsequently forming light guides in these films. The confinement of light in the guides will enhance the guided light power and could lead to devices based on phase change as above. However the chalcogenides have much faster and stronger responses to light, which can be engineered to be extremely effective through the waveguide structure allowing us to develop ultra-high speed optical switch elements, devices for converting between light wavelengths (changing the 'colour') and quantum light sources emitting photons in 'spookily connected' entangled pairs . By doping our waveguides with transition metals we expect to make lasers at a significant number of new wavelengths, particularly in the infrared region. Chalcogenide glass has higher transmission at much longer wavelengths than conventional glasses extending the laser applications to eyesafe rangefinders for aerospace, chemical sensing and specialist medical sensors.