Fully gapped topological surface states in Bi2Se3 films induced by a d-wave high-temperature superconductor

By E. Wang, Hao Ding, A. Fedorov, Wei Yao, Z. Li, Yan-Feng Lv, K. Zhao, Liguo Zhang, Zhijun Xu, J. Schneeloch and 10 more. Nature Physics, 2013

156 citations recorded by the source corpus.

By growing a topological insulator on top of a high-temperature superconducting substrate it is possible to induce superconductivity in the surface states of the topological insulator. Moreover, the pairing symmetry of the induced superconductivity is s-wave, unlike the d-wave symmetry of the substrate. Topological insulators are a new class of material1,2, that exhibit robust gapless surface states protected by time-reversal symmetry3,4. The interplay of such symmetry-protected topological surface states and symmetry-broken states (for example, superconductivity) provides a platform for exploring new quantum phenomena and functionalities, such as one-dimensional chiral or helical gapless Majorana fermions5, and Majorana zero modes6 that may find application in fault-tolerant quantum computation7,8. Inducing superconductivity on the topological surface states is a prerequisite for their experimental realization1,2. Here, by growing high-quality topological insulator Bi2Se3 films on a d-wave superconductor Bi2Sr2CaCu2O8+δ using molecular beam epitaxy, we are able to induce high-temperature superconductivity on the surface states of Bi2Se3 films with a large pairing gap up to 15 meV. Interestingly, distinct from the d-wave pairing of Bi2Sr2CaCu2O8+δ, the proximity-induced gap on the surface states is nearly isotropic and consistent with predominant s-wave pairing as revealed by angle-resolved photoemission spectroscopy. Our work could provide a critical step towards the realization of the long sought Majorana zero modes.

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

View Paper: https://www.semanticscholar.org/paper/d5f1441de09b2acf1eaaa12f6873425df4ab1b9e

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. Su-Yang Xu
2. M. Zahid Hasan
3. Tanmoy Das
4. Hsin Lin
5. Arun Bansil
6. G. Bian
7. Chen Fang
8. Nitin Samarth

In Condensed Matter Physics

1. Su-Yang Xu
2. Chen Fang
3. M. Zahid Hasan
4. Hsin Lin
5. G. Bian
6. Tanmoy Das
7. Arun Bansil

In Materials Chemistry

1. Tanmoy Das
2. Hsin Lin
3. Su-Yang Xu
4. Arun Bansil
5. M. Zahid Hasan
6. G. Bian
7. Chen Fang
8. Nitin Samarth

Citations in the corpus

• Angle-resolved photoemission studies of quantum materials (2020, unknown): “25(a)) (Chen et al., 2009a; Kasahara et al., 2010; Nandi et al., 2010; Parker et al., 2010; Wang et al., 2013a).”
• Colloquium : Topological band theory (2016, background): “Wang, E., H. Ding, A. V. Fedorov, W. Yao, Z. Li, Y.- F. Lv, K. Zhao, et al., 2013, “Fully Gapped Topological Surface States in Bi2Se3 Films Induced by a D-Wave High-Temperature Superconductor,” Nat.”
• Momentum-space imaging of Cooper pairing in a half-Dirac-gas topological superconductor (2014, result): “In that case, no superconducting coherence peak was observed [32–34], and the claim of a ≥ 15 meV leading edge shift [32] in the Dirac surface states in Bi2Se3/BSCCO is in contrast to the absence of any observable leading edge shift in the other two studies [33, 34].”