Associate Professor, Department of Physics, Korea University, South Korea

Biography: Dr. Donghun Lee is an experimentalist in the field of quantum optics and condensed matter physics. He earned Ph.D. degree at Ohio State University and did his postdoctoral research at Yale University and at University of California at Santa Barbara (UCSB). He is an associate professor at the department of physics at Korea University, South Korea since 2016. His research focuses on hybrid quantum systems and quantum sensing and imaging applications based on solid-state spin qubits i.e. nitrogen-vacancy defect centers in diamond.

Speech Title: Novel magnetic sensing and imaging with diamond defect-based qubits

Abstract: Probing and imaging magnetism at nanometer scale with high field sensitivity is of great interest in a wide range of fields, including solid-state physics, materials science and biomedical applications. In this talk, I will introduce a novel magnetic sensing and imaing method based on nitrogen-vacancy (NV) defect center in diamond. The diamond NV center has promising potential for nanometer and nanotesla magnetometry due to its atomic-scale size, long spin coherence times and high magnetic field sensitivity (e.g. < nT/Hz1/2). Since these properties are robust against a wide range of operating temperature, it is also suitable for studying novel magnetic materials exhibiting temperature-dependent magnetic orders. I will present basic working principle of magnetic field sensing and introduce scanning magnetometer combined with diamond NV center. I will also show some examples of sensing and imaging magnetic samples including permalloy, room temperature skyrmions.