Veranstaltungen
07. Oktober 2025, 16:00 bis 17:00
Peter Jacobson, School of Mathematics and Physics, The University of Queensland, Brisbane/Australia
Seminar
Introducing superconductivity into group IV elements by doping has long promised a pathway to introduce quantum functionalities into well-established semiconductor technologies. Recent progress with non-equilibrium hyperdoping has shown superconductivity in C, Si, and Ge, but the role of disorder and dopant clustering has obscured the origin of this effect. I will present our work on epitaxial growth of gallium-hyperdoped germanium films and trilayer heterostructures by molecular beam epitaxy. These films reach extreme hole concentrations, via nearly 18% Ga substitution, and display superconductivity with a transition temperature of 3.5 K. Using synchrotron X-ray absorption and scattering, we find that Ga atoms incorporate substitutionally in the Ge lattice, introducing a slight tetragonal distortion. First-principles calculations support these findings and point to the formation of a narrow band that enables superconductivity. Together, these results establish hyperdoped Ga:Ge as a structurally ordered superconductor–semiconductor platform suitable for quantum technologies.
J.A. Steele, P.J. Strohbeen, C. Verdi, A. Baktash, A. Danilenko, Y.-H. Chen, J. van Dijk, F.H. Knudsen, A. Leblanc, D. Perconte, L. Wang, E. Demler, S. Salmani-Rezaie, P. Jacobson, J. Shabani, “Superconductivity in Substitutional Ga-Hyperdoped Ge Epitaxial Thin Films” Nature Nanotechnology (in press), arXiv:2412.15421v2
Veranstaltung Details
- Veranstaltungsort
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SEM.R. DB gelb 05 B
1040 Wien
Wiedner Hauptstraße 8-10/E134 - Veranstalter
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IAP
Manuela Marik
marik@iap.tuwien.ac.at - Öffentlich
- Ja
- Kostenpflichtig
- Nein
- Anmeldung erforderlich
- Nein