Seminarium Fizyki Politechniki Wrocławskiej
PWr, bud. A1, sala 322
Induced superconductivity in core-shell semiconductor-superconductor nanowires
Prof. Andrei Manolescu
Reykjavik University, Iceland
In recent years, semiconductor nanowires coated with a thin shell of a metallic superconductor have been fabricated and studied experimentally. In such systems, the superconductivity can penetrate the semiconductor material, giving rise to complex quantum phenomena such as Andreev or Majorana bound states with topological properties. The semiconductor material, sometimes itself with a core-shell structure, becomes a superconductor, with charge carriers that retain the effective mass characteristic of the normal semiconductor. According to our recent calculations, performed at the Nanophysics Center at Reykjavik University https://www.ru.is/en/research-center/nano, the proximity induced superconductivity is strongly influenced by the quantum confinement of the electronic wave function within the transverse cross-section of the nanowire. In this regime, the concept of coherence length loses its meaning of a global parameter and instead it depends on the specific quantum states involved. The strength of the superconductivity induced in the semiconductor depends on the thickness and length of the nanowire, on the carrier concentration, and on the contact area with the metallic superconductor.
