Automated Analytical Investigations of Quantum Emission in Hexagonal Boron Nitride

Abstract

The next generation of computer security will depend on new levels of quantum mechanical in- teractions. These interactions can be made to occur on demand in such ways that their resultant properties are indeterminable without direct observation, and protocols for such transactions do not necessarily need to be Turing complete. This enables quantum emitters to rapidly meet these growing demands. One important distinction in quantum emitters over conventional light sources is their in- distinguishable and pure emission from one reliable atomic interaction. Recently, room-temperature single-photon emission has been demonstrated in hexagonal boron nitride (hBN). While its emis- sion is still poorly understood, it’s room-temperature appeal would significantly lower operating costs compared to leading competitors like quantum dots, which must be cooled to liquid nitrogen temperatures or below to operate reliably. Any engineering efforts to improve emission efficiency and purity in hBN require a more informed understanding of the available excitation and relax- ation mechanisms involved in and around optical transitions. These understandings are gained from multiple characterization techniques to probe the underlying energy structure, and are especially important in building analytical models for and designing 2D and other lower-dimensional proto- types. This thesis investigates an automated mechanism to quantify and correlate measurements in hBN that reveal its single-photon emission. Specifically, bulk photoluminescence measurements are used to screen candidates for potential quantum emission, which can be further investigated with Hanbury–Brown Twiss interferometry to validate their single-photon nature. The tools and analysis used in this investigation translate well to other material investigations.