Unveiling and controlling quantum point defects in oxides
Abstract
Point defects in crystals are recognized as one of the most promising platforms for quantum sensing and quantum networking applications. The overarching goal of our research is to develop the next generation of point defects in wide band gap oxides. Defects will exhibit excellent optical and spin coherence properties enabled by (1) ultra-high purity molecular-beam epitaxial host synthesis, (2) defect synthesis and spectroscopy of shallow donor and rare-earth ion impurities, (3) advanced single atom scanning transmission electron microscopy (STEM) for structural imaging and STEM spectroscopy, and (4) advanced ab initio frameworks to accelerate point-defect discovery for quantum information science and technology. The success of the defect-host combination depends on the crystal structure, defect structure, and further defects in the microscopic environment. The parameter space to engineer the crystal host-defect-environment is vast, and the efficient exploration of this space requires the development of tools and analytical techniques that are currently beyond state-of-the-art. We will develop these tools within the framework of two aims- Aim 1- Advancing the oxide host and Aim 2- Defect synthesis and discovery. We will (1) achieve record-breaking spin coherence times for donors in ZnO, enabled by the first realization of chemically and isotopically pure ZnO, thus approaching the fundamental limitations of seconds for electron spins and exceeding minutes for nuclear spins, (2) develop high purity hosts with low nuclear spin for rare-earth ions (REIs) like ZnO and CeO2 enabling lifetime-limited optical coherence and longer spin coherence compared to state of the art and (3) predict and synthesize new quantum defects in ZnO or MgO based impurity-vacancy complexes. Theoretical frameworks, synthesis, spectroscopic and imaging techniques are expected to reach beyond the targeted quantum defects in ZnO, MgO and CeO2 hosts to broadly advance our understanding and control of the defect-oxide host system.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310418
Entities
People
- Kai-Mei Fu
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Washington