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تسجيل مستخدم جديدErasable superconductivity in topological insulator Bi2Se3 induced by voltage pulse
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Three-dimensional topological insulators (TIs) attract much attention due to its topologically protected Dirac surface states. Doping into TIs or their proximity with normal superconductors can promote the realization of topological superconductivity(SC) and Majorana fermions with potential applications in quantum computations. Here, an emergent superconductivity was observed in local mesoscopic point-contacts on the topological insulator Bi2Se3 by applying a voltage pulse through the contacts, evidenced by the Andreev reflection peak in the point-contact spectra and a visible resistance drop in the four-probe electrical resistance measurements. More intriguingly, the superconductivity can be erased with thermal cycles by warming up to high temperatures (300 K) and induced again by the voltage pulse at the base temperature (1.9 K), suggesting a significance for designing new types of quantum devices. Nematic behaviour is also observed in the superconducting state, similar to the case of CuxBi2Se3 as topological superconductor candidates.
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a Josephson supercurrent, and demonstrates a gap-like structure in the conductance spectra as probed by a normal-metal electrode. The establishment of the gap is not by confining the electrons into a narrow space close to the superconductor-normal metal interface, as previously observed in other systems, but presumably via electron-electron attractive interaction in Bi2Se3.
We present an in-depth classification of the topological phases and Majorana fermion (MF) excitations that arise from the bulk interplay between unconventional multiband spin-singlet superconductivity and various magnetic textures. We focus on magnet
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Strontium intercalation between van der Waals bonded layers of topological insulator Bi2Se3 is found to induce superconductivity with a maximum Tc of 2.9 K. Transport measurement on single crystal of optimally doped sample Sr0.1Bi2Se3 shows weak anis
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