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Effects of Parity and Symmetry on the Aharonov-Bohm Phase of a Quantum Ring.

ABSTRACT: We experimentally investigate the properties of one-dimensional quantum rings that form near the surface of nanowire quantum dots. In agreement with theoretical predictions, we observe the appearance of forbidden gaps in the evolution of states in a magnetic field as the symmetry of a quantum ring is reduced. For a twofold symmetry, our experiments confirm that orbital states are grouped pairwise. Here, a π-phase shift can be introduced in the Aharonov-Bohm relation by controlling the relative orbital parity using an electric field. Studying rings with higher symmetry, we note exceptionally large orbital contributions to the effective g-factor (up to 300), which are many times higher than those previously reported. These findings show that the properties of a phase-coherent system can be significantly altered by the nanostructure symmetry and its interplay with wave function parity.

SUBMITTER: Debbarma R

PROVIDER: S-EPMC8759086 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Effects of Parity and Symmetry on the Aharonov-Bohm Phase of a Quantum Ring.

Debbarma Rousan R Potts Heidi H Stenberg Calle Janlén CJ Tsintzis Athanasios A Lehmann Sebastian S Dick Kimberly K Leijnse Martin M Thelander Claes C

Nano letters 20211215 1

We experimentally investigate the properties of one-dimensional quantum rings that form near the surface of nanowire quantum dots. In agreement with theoretical predictions, we observe the appearance of forbidden gaps in the evolution of states in a magnetic field as the symmetry of a quantum ring is reduced. For a twofold symmetry, our experiments confirm that orbital states are grouped pairwise. Here, a π-phase shift can be introduced in the Aharonov-Bohm relation by controlling the relative o ...[more]

PMID: 34910870

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