Quantum Hall states observed in thin films of Dirac semimetal Cd3As2

Abstract

A well known semiconductor Cd3As2 has reentered the spotlight due to its unique electronic structure and quantum transport phenomena as a topological Dirac semimetal. For elucidating and controlling its topological quantum state, high-quality Cd3As2 thin films have been highly desired. Here we report the development of an elaborate growth technique of high-crystallinity and high-mobility Cd3As2 films with controlled thicknesses and the observation of quantum Hall effect dependent on the film thickness. With decreasing the film thickness to 10 nm, the quantum Hall states exhibit variations such as a change in the spin degeneracy reflecting the Dirac dispersion with a large Fermi velocity. Details of the electronic structure including subband splitting and gap opening are identified from the quantum transport depending on the confinement thickness, suggesting the presence of a two-dimensional topological insulating phase. The demonstration of quantum Hall states in our high-quality Cd3As2 films paves a road to study quantum transport and device application in topological Dirac semimetal and its derivative phases.

24 pages, 4 figures + supplementary 13 pages, 13 figures

References in corpus (5)

• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Classification of stable three-dimensional Dirac semimetals with nontrivial topology
• Quantum transport evidence for a three-dimensional Dirac semimetal phase in Cd3As2
• Linear magnetoresistance caused by mobility fluctuations in the n-doped Cd3As2

Cited by in corpus (17)

• Topological Semimetal Nanostructures: From Properties to Topotronics
• Field-Tunable One-Sided Higher-Order Topological Hinge States in Dirac Semimetals
• Perspective: 3D quantum Hall effect
• Molecular beam epitaxy of three-dimensionally thick Dirac semimetal Cd3As2 films
• Ferromagnetic state above room temperature in a proximitized topological Dirac semimetal
• Basal-plane growth of cadmium arsenide by molecular beam epitaxy
• Quantum Hall effect originated from helical edge states in Cd${}_3$As${}_2$
• Anisotropic three-dimensional quantum Hall effect and magnetotransport in mesoscopic Weyl semimetals
• Absence of signatures of Weyl orbits in the thickness dependence of quantum transport in cadmium arsenide
• Strain-gradient induced topological transition in bent nanoribbons of the Dirac semimetal Cd3As2
• Enhancement of spin-orbit coupling in Dirac semimetal Cd${}_3$As${}_2$ films by Sb-doping
• Integer quantum Hall effect and enhanced g-factor in quantum confined Cd3As2 films
• Challenges to magnetic doping of thin films of the Dirac semimetal Cd${}_3$As${}_2$
• Molecular beam deposition of a new layered pnictide with distorted Sb square nets
• Microwave response in a topological superconducting quantum interference device
• Nodal lines and boundary modes in topological Dirac semimetals with magnetism
• Edge and bulk states in Weyl-orbit quantum Hall effect as studied by Corbino measurements