# Electronic structure and relaxation dynamics in a superconducting topological material

@article{Neupane2016ElectronicSA, title={Electronic structure and relaxation dynamics in a superconducting topological material}, author={Madhab Neupane and Yukiaki Ishida and Raman Sankar and Jian-Xin Zhu and D. Sevilla Sanchez and Ilya Belopolski and Su-Yang Xu and Nasser Alidoust and Md Mofazzel Hosen and Shik Shin and F. C. Chou and M Zahid Hasan and Tomasz Durakiewicz}, journal={Scientific Reports}, year={2016}, volume={6} }

Topological superconductors host new states of quantum matter which show a pairing gap in the bulk and gapless surface states providing a platform to realize Majorana fermions. Recently, alkaline-earth metal Sr intercalated Bi2Se3 has been reported to show superconductivity with a Tc ~ 3 K and a large shielding fraction. Here we report systematic normal state electronic structure studies of Sr0.06Bi2Se3 (Tc ~ 2.5 K) by performing photoemission spectroscopy. Using angle-resolved photoemission…

## 20 Citations

Discovery of topological nodal-line fermionic phase in a magnetic material GdSbTe

- Medicine, PhysicsScientific Reports
- 2018

The experimental discovery of an antiferromagnetic topological nodal-line semimetallic state in GdSbTe is reported using angle-resolved photoemission spectroscopy and the detailed electronic structure of the paramagnetic state is revealed.

Drive the Dirac electrons into Cooper pairs in Sr x Bi 2 Se 3

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Drive the Dirac electrons into Cooper pairs in SrxBi2Se3

- Physics, MedicineNature communications
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The systematic study of scanning tunnelling microscope/spectroscopy on the possible topological superconductor SrxBi2Se3 shows that only the intercalated Sr atoms can induce superconductivity and finds that the surface Dirac electrons will simultaneously condense into the superconducting state within thesuperconducting gap.

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- Physics, MedicineScientific reports
- 2016

Surprisingly, field-angle dependent magnetotransport measurements reveal a large anisotropy of Bc2 when the magnet field is rotated in the basal plane, which indicates unconventional superconductivity with odd-parity spin-triplet Cooper pairs recently proposed for rhombohedral topological superconductors.

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- Materials Science
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Abstract Topological insulators (TIs) characterized by gapless and spin-polarized conical band dispersion on their surfaces have been extensively studied over the last decade. This article reviews…

Degradation of topological surface state by nonmagnetic S doping in SrxBi2Se3

- Materials Science, MedicineScientific reports
- 2017

A detailed investigation on the lattice structure, electronic and magnetic properties, as well as the topological superconducting properties of SrxBi2Se3−ySy samples is reported, finding that thesuperconducting transition temperature keeps nearly unchanged in all samples, despite of a gradual decrease of the super Conducting shielding volume fraction with increasing S doping content.

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- 2018

An archetypical layered topological insulator Bi$_2$Se$_3$ becomes superconductive upon doping with Sr, Nb or Cu. Superconducting properties of these materials in the presence of in-plane magnetic…

Muon spin rotation study of the topological superconductor Sr x Bi 2 Se 3

- Physics
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We report transverse-field (TF) muon spin rotation experiments on single crystals of the topological superconductor Srx Bi2 Se3 with nominal concentrations x = 0.15 and 0.18 (Tc ∼ 3 K). The TF…

## References

SHOWING 1-10 OF 64 REFERENCES

Experimental evidence for s-wave pairing symmetry in superconducting Cu(x)Bi2Se3 single crystals using a scanning tunneling microscope.

- Physics, MedicinePhysical review letters
- 2013

The tunneling spectrum shows that the density of states at the Fermi level is fully gapped without any in-gap states, which suggests that Cu(x)Bi(2)Se(3) is a classical s-wave superconductor contrary to previous expectations and measurements.

Electronic structure of a superconducting topological insulator Sr-doped Bi2Se3

- Materials Science, Physics
- 2015

Using high-resolution angle-resolved photoemission spectroscopy and scanning tunneling microscopy/spectroscopy, the atomic and low energy electronic structure of the Sr-doped superconducting…

Surface electronic structure of the topological Kondo-insulator candidate correlated electron system SmB6.

- Physics, MedicineNature communications
- 2013

The authors' observed in-gap Fermi surface oddness tied with the Kramers' point topology, their coexistence with the two-dimensional transport anomaly in the Kondo hybridization regime, as well as their robustness against thermal recycling, collectively provide strong evidence for protected surface metallicity with a Fermani surface whose topology is consistent with the theoretically predicted topological FermI surface.

The Coexistence of Superconductivity and Topological Order in the Bi2Se3 Thin Films

- Physics, MedicineScience
- 2012

A thin layer of a topological insulator grown on the surface of a superconductor is shown to acquire a superconducting gap, laying the groundwork for experimentally realizing Majorana fermions in condensed matter physics.

A topological Dirac insulator in a quantum spin Hall phase

- Physics, MedicineNature
- 2008

The direct observation of massive Dirac particles in the bulk of Bi0.9Sb0.1 is reported, which suggests that the observed surface state on the boundary of the bulk insulator is a realization of the ‘topological metal’, which has potential application in developing next-generation quantum computing devices that may incorporate ‘light-like’ bulk carriers and spin-textured surface currents.

Measurement of an exceptionally weak electron-phonon coupling on the surface of the topological insulator Bi2Se3 using angle-resolved photoemission spectroscopy.

- Materials Science, MedicinePhysical review letters
- 2012

An extremely weak broadening of the topological surface state with temperature and no anomalies in the state's dispersion is found, indicating exceptionally weak electron-phonon coupling, suggesting that topological insulators could serve as a basis for room-temperature electronic devices.

Pressure-induced superconductivity in topological parent compound Bi2Te3

- Materials Science, PhysicsProceedings of the National Academy of Sciences
- 2010

The results suggested that topological superconductivity can be realized in Bi2Te3 due to the proximity effect between superconducting bulk states and Dirac-type surface states.

Ultrafast electron dynamics at the Dirac node of the topological insulator Sb2Te3

- Physics, MedicineScientific reports
- 2015

This work explores the surface Dirac fermion dynamics in the TI Sb2Te3 by time- and angle-resolved photoemission spectroscopy (TrARPES) and finds an in-gap DP located completely above the Fermi energy (EF).

Emergent quantum confinement at topological insulator surfaces.

- Physics, MedicineNature communications
- 2012

It is demonstrated that a conceptually simple model, implementing a semiconductor-like band bending in a parameter-free tight-binding supercell calculation, can quantitatively explain the entire measured hierarchy of electronic states.

Topological Superconductivity in CuxBi2Se3

- Physics
- 2011

A topological superconductor (TSC) is characterized by the topologically-protected gapless surface state that is essentially an Andreev bound state consisting of Majorana fermions. While a TSC has…