凝態理論seminar
Supercurrent Diode: A Sensitive Symmetry Probe and Symmetry-Augmented Device
演講者 : Dr. Hung-Yu Yang - (Department of Electrical and Computer Engineering, University of California, Los Angeles)
演講地點 :
理學教學新大樓物理系 5F 多功能交誼廳
演講時間 :
2024 / 09 / 11
16:00
A supercurrent diode exhibits different critical current magnitudes for opposite current directions. This effect is closely tied to the symmetry of the superconducting state, and serves as a new probe for unconventional superconductivity. For iron chalcogenides superconductors, we observed a field-free supercurrent diode effect in a van der Waals (vdW) Josephson junction (JJ) composed of Fe(Te,Se), providing clear evidence of time-reversal symmetry breaking. This finding establishes the essential symmetry requirement for Majorana bound states to emerge at zero field in Fe(Te,Se) from a new perspective. Beyond revealing fundamental symmetry properties, supercurrent rectification offers practical applications in cryogenic electronics, akin to semiconductor diodes. By integrating a multiferroic barrier into a vdW JJ, we strategically designed the symmetry of the JJ to augment the diode’s field resilience. This design enables the supercurrent diode to withstand stray fields up to industrial standards for the first time. These advancements in supercurrent diode research and vdW JJs hold significant implications for quantum computing.
Bio: Dr. Hung-Yu Yang is a postdoctoral researcher at the University of California, Los Angeles. He received his B.S. in Physics from National Tsing Hua University, and Ph.D. in Physics from Boston College. He has authored and co-authored over 20 research papers in high-quality peer-reviewed journals, including Nature Materials, Nature Communications, Physical Review Letters, Physical Review B, etc. He actively serves the scientific community as an APS Career Mentoring Fellow, invited speaker and session chair of APS March Meeting, reviewer for international journals and government funding agencies. His research focuses on engineering topological quantum states by combining electronic band topology, magnetism, and superconductivity. His work aims to advance our understanding of quantum materials and pave the way for new quantum technologies, such as robust quantum computers and cryogenic electronic devices.
Bio: Dr. Hung-Yu Yang is a postdoctoral researcher at the University of California, Los Angeles. He received his B.S. in Physics from National Tsing Hua University, and Ph.D. in Physics from Boston College. He has authored and co-authored over 20 research papers in high-quality peer-reviewed journals, including Nature Materials, Nature Communications, Physical Review Letters, Physical Review B, etc. He actively serves the scientific community as an APS Career Mentoring Fellow, invited speaker and session chair of APS March Meeting, reviewer for international journals and government funding agencies. His research focuses on engineering topological quantum states by combining electronic band topology, magnetism, and superconductivity. His work aims to advance our understanding of quantum materials and pave the way for new quantum technologies, such as robust quantum computers and cryogenic electronic devices.
