Sensing and Imaging
Atom-scale impurities in solids can trap individual electrons, forming analogs of molecules in free space. Particularly in wide-bandgap semiconductors like diamond, the quantum coherence of such trapped electron spins can be remarkably long lived, even at room temperature, and individual defect spins can be controlled using optics and electronics. A prime example is the nitrogen-vacancy (NV) center in diamond, which shows promise as an optically-addressable quantum bit in future technologies for quantum information processing and nanoscale sensing. Harnessing the versatility of semiconductor fabrication technology, we aim to realize practical implementations of quantum technologies based on such systems.
Phys. Rev. Applied, 13 , pp. 024016, 2020.
Micromachines, 9 , pp. 437, 2018.
Sensing and Imaging
Highly localized, optically controllable spins can serve as remote sensors of their nanoscale environment, providing detailed information about their local conditions such as magnetic and electric fields, crystal strain, and temperature. This capability suggests many exciting applications, particularly in materials science, chemistry, and biology, where the ability to monitor fields and their dynamics on nanometer length scales could lead to breakthroughs in understanding protein dynamics, cellular communication, and complex quantum materials. We are developing quantum sensing applications and integrated quantum sensing platforms based on spins in solids.
ACS Nano, 12 , pp. 4678-4686, 2018.
Point defects in wide bandgap semiconductors, like the NV center in diamond, have emerged as leading platforms for quantum technologies, providing optically and electronically addressable spin states that are robust to environmental noise. However, identification of new defect systems in new host materials is generally a slow, ad hoc process. Because the desired operating parameters for these defect systems are application-specific and depend heavily on the materials involved, we are focused on combining new computational and experimental techniques to accelerate the discovery of defect-host systems that are optimized for spin-light quantum interfaces.
Quantum-mechanical effects become progressively more important in materials with reduced dimensions, offering both a challenge for the continued miniaturization of traditional electronics and an opportunity for developing new quantum technologies. Our group combines optical and electrical techniques to study new materials systems in both bulk and low-dimensional (0D, 1D, 2D) samples, particularly in semiconducting “beyond-carbon” materials such as boron nitride. These emerging materials offer many of the appealing features of their carbon counterparts but with additional advantages, particularly for optical measurements. We are interested in both the fundamental physics of these materials and their potential as electrical & optical components, sensors, and in quantum information technology.
ACS Photonics, 7 , pp. 288-295, 2019.
Nature Communications, 10 (222), 2019.
The atomic scales and high refractive index environments of solid state quantum emitters prevent their detection without bulky free-space optical setups. Condensed optical tools will be required to replace these traditional setups in integrated devices that rely on solid state quantum emitters. An example of such a tool is the immersion metalens that our lab has fabricated and is now improving through fabrication-constrained inverse design techniques.
Nature Communications, 10 (2392), 2019.
APL Photonics, 1 , pp. 071302, 2016.