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Induced superconductivity in the three-dimensional topological insulator HgTe
Luis Maier1, Jeroen B Oostinga, Daniel Knott
1Physikalisches Institut, EP3, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
Physical Review Letters
|December 11, 2012
Summary
We observed a precursor to the Josephson effect in the topological surface states of mercury telluride (HgTe) using niobium (Nb) superconductor. This demonstrates proximity-induced superconductivity in HgTe surface states.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Mercury telluride (HgTe) is a three-dimensional topological insulator.
- Electronic transport in HgTe is dominated by its surface states.
Purpose of the Study:
- Investigate Josephson junctions using HgTe and niobium (Nb).
- Explore proximity-induced superconductivity in HgTe topological surface states.
Main Methods:
- Fabrication of HgTe-based Josephson junctions with Nb.
- Transport measurements, including differential resistance.
- Application of magnetic fields to observe oscillations.
Main Results:
- Observed a strong zero-bias anomaly in differential resistance, indicating proximity-induced superconductivity.
- Detected Fraunhofer-like oscillations in differential resistance with applied magnetic field.
- Demonstrated a precursor of the Josephson effect in HgTe topological surface states.
Conclusions:
- Proximity-induced superconductivity is established in the topological surface states of HgTe.
- HgTe topological surface states can support precursors of the Josephson effect, paving the way for topological quantum devices.
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