Superconductor-Semiconductor Epitaxy for Integrated Quantum Electronics
April 24 (Thursday), 2025
11:30 am to 12:30 pm (EDT)
Virtual via Zoom
Abstract: Introducing superconductivity into Group IV elements by doping has long promised a pathway to introduce quantum functionalities into well-established semiconductor technologies. Non-equilibrium hyperdoping of Group III atoms into Si or Ge has successfully shown superconductivity can be achieved, however, the origin of superconductivity has been obscured by structural disorder and dopant clustering. Here, we report the epitaxial growth of hyperdoped Ga:Ge films by molecular beam epitaxy with extreme hole concentrations 10^21cm^-3, yielding superconductivity with a critical temperature of 3.5K. Our findings, corroborated by first-principles calculations, suggest that the structural order of Ga dopants creates a narrow band for the emergence of superconductivity in Ge, establishing hyperdoped Ga:Ge as a low-disorder, epitaxial superconductor-semiconductor platform. This platform opens up a new path for integration of superconductivity for cryogenic and quantum applications in Group IV.
Biography: Dr. Javad Shabani is Professor of Physics, and Director of the Center for Quantum Information Physics at New York University. He received his PhD from Princeton University in 2011. After two years of research on semiconductor-based qubits at Harvard University, he joined UC Santa Barbara. There, he worked closely with Microsoft research on hybrid semiconductors/superconductors heterostructures to study topological superconductivity. He is an expert in quantum materials and devices for computation technologies. He has been honored with the US Air Force Young Investigator Award, and the US Army Young Investigator Award, both in 2016.