Magnetoconductance Oscillations in Topological Crystalline Insulator Nanowires.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41054918.
- Also identified by DOI 10.1021/acs.nanolett.5c02643 and PMC identifier 12532288.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Pb<sub>1-<i>x</i></sub>Sn<sub><i>x</i></sub>Te is a topological crystalline insulator (TCI) hosting topological surface and hinge states protected by crystal mirror symmetries. The bulk carrier density can be reduced by tuning the Sn ratio <i>x</i>. Here, we perform low-temperature magnetotransport measurements on Pb<sub>1-<i>x</i></sub>Sn<sub><i>x</i></sub>Te nanowires with varying <i>x</i> values grown by molecular beam epitaxy. We observe signatures of Aharonov-Bohm (AB)-type oscillations for 0.32 ≤ <i>x</i> ≤ 0.51, which coexist with aperiodic universal conductance fluctuations (UCFs) and are consistent with phase-coherent transport on the nanowire surface. We separately analyze the temperature dependence of the AB-type oscillations and UCFs. The oscillations give a phase coherence length of <i>l</i><sub>ϕ</sub> = 1.4 ± 0.2 μm at 80 mK, consistent with the ballistic transport regime. The UCF provides a significantly smaller <i>l</i><sub>ϕ</sub>, consistent with a diffusive bulk transport channel, parallel to the ballistic surface. Our results indicate the presence of phase-coherent surface states on Pb<sub>1-<i>x</i></sub>Sn<sub><i>x</i></sub>Te nanowires with 0.32 ≤ <i>x</i> ≤ 0.51.