Chiral transport along magnetic domain walls in the quantum anomalous Hall effect

Journal Article · Fri Dec 01 00:00:00 EST 2017 · npj Quantum Materials

DOI:https://doi.org/10.1038/s41535-017-0073-0· OSTI ID:1408888

Rosen, Ilan T. ^[1]; Fox, Eli J. ^[2]; Kou, Xufeng ^[3]; Pan, Lei ^[4]; Wang, Kang L. ^[4]; Goldhaber-Gordon, David ^[2]

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1. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES); SLAC
2. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States). Stanford Institute for Materials and Energy Science (SIMES)
3. Univ. of California, Los Angeles, CA (United States); ShanghaiTech Univ., Shanghai (China)
4. Univ. of California, Los Angeles, CA (United States)

The recent prediction, and subsequent discovery, of the quantum anomalous Hall (QAH) effect in thin films of the three-dimensional ferromagnetic topological insulator (MTI) (Cr$$_y$$Bi$$_x$$Sb$$_{1-x-y}$$)$$_2$$Te$$_3$$ has opened new possibilities for chiral-edge-state-based devices in zero external magnetic field. Like the $$\nu=1$$ quantum Hall system, the QAH system is predicted to have a single chiral edge mode circulating along the boundary of the film. Backscattering of the chiral edge mode should be suppressed, as recently verified by the observation of well-quantized Hall resistivities $$\rho_{yx} = \pm h/e^2$$, along with longitudinal resistivities as low as a few ohms. Dissipationless 1D conduction is also expected along magnetic domain walls. Here, we intentionally create a magnetic domain wall in a MTI and study electrical transport along the domain wall. We present the first observation of chiral transport along domain walls, in agreement with theoretical predictions. We present further evidence that two modes equilibrate and co-propagate along the length of the domain wall.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States)
• Sponsoring Organization: Gordon and Betty Moore Foundation; National Science Foundation (NSF); US Army Research Office (ARO); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC02-76SF00515
• OSTI ID: 1408888
• Journal Information: npj Quantum Materials, Journal Name: npj Quantum Materials Journal Issue: 1 Vol. 2; ISSN 2397-4648
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Quantum Hall
Topological insulators