Research Projects

Motivation: Single-photon emitters (SPEs) are critical to many quantum technologies including quantum cryptography, quantum computing, quantum communication. While an ideal on-demand SPE has yet to be realized, numerous promising material systems have emerged. Progress have been made beyond proof-of-concept to engineering-focused development, with continuous improvements in performance. These systems are becoming more reliable and scalable, approaching the demands of practical quantum applications like communication networks and quantum computers. A SPE generates one photon at a time with a specific energy. These photons consist of two optical modes with perpendicular polarizations. These properties are crucial for applications in quantum information, as they enable complex quantum operations and secure communication. We propose designing and fabricating nanostructures coupled with 2D TMD layers to confine quantum states within the 2D layers, enabling the creation of emitter arrays for scalable SPEs integrated into photonic platforms. Significance — Bright, stable, and controllable SPEs are vital for various quantum technologies, including quantum computing, cryptography, secure communication, metrology, precision measurement, quantum simulations, and optical quantum networks. Creating bright and stable single-photon emitters in atomically thin TMDs, other 2D van der Waals materials, and heterostructures shows a significant advancement in photonics and quantum information technologies. Their 2D nature offers unique advantages, such as mechanical flexibility and surface-level emitter localization, enabling innovative strategies for SPE creation, positioning, and control, including strain tuning and integration with photonic platforms. Research Question — A key question is in developing quantum emitters is: How can we create high quality, bright, stable and controllable single photons source by engineering quantum confinement in 2D material? Solid-state emitters like NV centers and quantum dots host bright emitters but encounter challenges such as spectral diffusion and integration issues with photonic structures. Our project aims to create stable SPEs in 2D layered materials on patterned substrates, using annealing and electric field control to improve stability. Aim and Approach — The project aims to create stable and controllable SPEs by leveraging recent advancements in generating these emitters in 2D layers. It involves applying strain and electric fields on optimized heterostructures. The project will use optical spectroscopy, including micro-photoluminescence, to monitor light-matter interaction, exciton, and charge dynamics. The second-order correlation function, g(2)(τ), will be measured to characterize single-photon emission. The project will include the long-term performance, stability, and reproducibility of SPEs. In a dual-gated device, Stark effect will provide energy tunabilty, and doping density will control emitter switching.