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Heavy-Hole States in Germanium Hut Wires.

ABSTRACT: Hole spins have gained considerable interest in the past few years due to their potential for fast electrically controlled qubits. Here, we study holes confined in Ge hut wires, a so-far unexplored type of nanostructure. Low-temperature magnetotransport measurements reveal a large anisotropy between the in-plane and out-of-plane g-factors of up to 18. Numerical simulations verify that this large anisotropy originates from a confined wave function of heavy-hole character. A light-hole admixture of less than 1% is estimated for the states of lowest energy, leading to a surprisingly large reduction of the out-of-plane g-factors compared with those for pure heavy holes. Given this tiny light-hole contribution, the spin lifetimes are expected to be very long, even in isotopically nonpurified samples.

SUBMITTER: Watzinger H

PROVIDER: S-EPMC5108027 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Heavy-Hole States in Germanium Hut Wires.

Watzinger Hannes H Kloeffel Christoph C Vukušić Lada L Rossell Marta D MD Sessi Violetta V Kukučka Josip J Kirchschlager Raimund R Lausecker Elisabeth E Truhlar Alisha A Glaser Martin M Rastelli Armando A Fuhrer Andreas A Loss Daniel D Katsaros Georgios G

Nano letters 20161017 11

Hole spins have gained considerable interest in the past few years due to their potential for fast electrically controlled qubits. Here, we study holes confined in Ge hut wires, a so-far unexplored type of nanostructure. Low-temperature magnetotransport measurements reveal a large anisotropy between the in-plane and out-of-plane g-factors of up to 18. Numerical simulations verify that this large anisotropy originates from a confined wave function of heavy-hole character. A light-hole admixture o ...[more]

PMID: 27656760

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