We live in the midst of an information technology revolution. In the last few decades, with the aggressive scaling of electronic devices, we have realized unprecedented performance in computing and communication. However, this rapid scaling, commonly known as "Moore's Law" is slowing and it is well-understood that next-generation computing technology will rely heavily on data centers and cloud computing. We are already experiencing this trend with the increased investment from large technology companies in these sectors. To support this architecture, however, we need to bring optical interconnect technology, which is the backbone of the modern internet, to shorter length scales. These optical devices need to operate at extremely low power. Going beyond traditional computing and communication, quantum technology presents a paradigm shift in the way we think about information technology. Extremely low-power optical devices can also provide solutions for these quantum technologies. In our research, we will develop photonic integrated circuits, similar to electronic integrated circuits, integrated with single atom thick 2D materials to create these low-power optical devices. Specifically, we will be using atomic defects in 2D materials to push the energy to the single photon level, which is the lowest conceivable energy in photonics, and almost a million times smaller compared to energy consumption in existing optical devices. Our work will bring the innovations in atomic physics to chip-scale technology, and with 2D materials, it is possible to develop these low power devices in a silicon platform exploiting the same fabrication technology which is used to manufacture today's computers and smart phones.
Classical and quantum signal processing using light has been a long-standing goal for scientists and engineers. Recent progress in micro- and nano-scale optical devices has renewed interest in this subject, as it can allow pushing energy consumption to regimes that have not been attainable in bulk optical systems. Specifically, by exploiting nanoscale optical cavities and single quantum emitters, the potential exists for building photonic devices based on principles of quantum electrodynamics. However, in all the existing cavity quantum electrodynamic devices, the single emitters are embedded in a 3D-substrate, rendering external control and facial integration with existing electronic and photonic platforms difficult. These limitations can be circumvented by using a quantum emitter in a 2D substrate, such as single emitters in monolayer materials like transition metal dichalcogenides. The unprecedented material compatibility of monolayer materials will also allow building these quantum optical devices using scalable CMOS technologies. The current proposal aims to research and develop a solid-state cavity quantum electrodynamic platform with single quantum emitters embedded in monolayer materials coupled to integrated solid-state nano-scale cavities. Combining numerical simulation, device fabrication, and optical characterization, the research thrusts include: (i) measure Purcell enhancement with a tunable 2D emitter-cavity system; (ii) demonstrate cavity-enhanced light emitting diodes and (iii) observe strong coupling cavity quantum electrodynamic effects. The ultimate goal is to demonstrate electronically tunable strongly coupled emitter-cavity system, where electro-optic and all-optical switching can be performed at a single photon energy level, and non-classical light can be generated exploiting strong correlation between photons.
