Magnetic modulation doping in topological insulators toward higher-temperature quantum anomalous Hall effect

By M. Mogi, R. Yoshimi, A. Tsukazaki, K. Yasuda, Y. Kozuka, Kei S. Takahashi, Masashi Kawasaki, Y. Tokura. 2015

321 citations recorded by the source corpus.

Quantum anomalous Hall effect (QAHE), which generates dissipation-less edge current without external magnetic field, is observed in magnetic-ion doped topological insulators (TIs), such as Cr- and V-doped (Bi,Sb)2Te3. The QAHE emerges when the Fermi level is inside the magnetically induced gap around the original Dirac point of the TI surface state. Although the size of gap is reported to be about 50 meV, the observable temperature of QAHE has been limited below 300 mK. We attempt magnetic-Cr modulation doping into topological insulator (Bi,Sb)2Te3 films to increase the observable temperature of QAHE. By introducing the rich-Cr-doped thin (1 nm) layers at the vicinity of the both surfaces based on non-Cr-doped (Bi,Sb)2Te3 films, we have succeeded in observing the QAHE up to 2 K. The improvement in the observable temperature achieved by this modulation-doping appears to be originating from the suppression of the disorder in the surface state interacting with the rich magnetic moments. Such a superlattice designing of the stabilized QAHE may pave a way to dissipation-less electronics based on the highertemperature and zero magnetic-field quantum conduction.

Subfields: Atomic and Molecular Physics, and Optics, Condensed Matter Physics, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/90415a884ffca7fa30458106e8d29b0ce1a6ff99

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

1. Chaoxing Liu
2. Cui-Zu Chang
3. Allan H. MacDonald
4. Ashvin Vishwanath
5. M. Koshino
6. Takashi Taniguchi
7. Kenji Watanabe

In Condensed Matter Physics

1. Chaoxing Liu
2. Cui-Zu Chang
3. Allan H. MacDonald

In Materials Chemistry

1. Chaoxing Liu
2. Cui-Zu Chang
3. Allan H. MacDonald
4. Ashvin Vishwanath
5. M. Koshino

Citations in the corpus

• Colloquium : Quantum anomalous Hall effect (2022, background): “As a result, the critical temperature of the QAH states in these modulation-doped tri- and penta-layer heterostructures is ∼10 K (Mogi et al., 2015).”