Where imperfections lead to opportunity: Points defects in SiC with photonic and spin applications
Evelyn Hu, Harvard University, Cambridge, USA
There is often a natural assumption that “perfect form” of a material is required to produce “perfect functioning” of a device, where the function may relate to precision sensing, or the storing or transmission of information. Recently, however, there has been excitement about the performance of defects in crystalline semiconductors such as diamond and SiC. The defects are deviations from perfect, periodic crystalline order, yet can manifest optical emission at a variety of wavelengths, distinctively coupled to long spin coherence times. Thus, such defects can provide a wealth of new opportunities for compact, integrable photonic sources and also serve as promising candidates for quantum information applications. This talk will focus on our use of nanobeam photonic crystal cavities, fabricated from 4H-SiC, which achieved an 80-fold optical enhancement of a Si-vacancy transition with emission at about 860 nanometers. The high quality cavities can serve as exquisitely selective optical amplifiers of defects in SiC, as well as “nanoscopes” into the material, allowing us to learn about the details of an atomic environment.