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Geneva Researchers Measure Quantum Metric in Sb2Te3

5/28/2026

Summary

Geneva Researchers Measure

University of Geneva researchers measured the quantum metric in the three-dimensional topological insulator antimony-telluride (Sb2Te3).
Giacomo Sala and Andrea Caviglia led the experiment, published in *Nature Materials*.
The result confirms theory that the quantum metric shapes transport beyond Berry curvature and extends 2025 strontium-titanate/lanthanum-aluminate work.
Collaboration with Salerno, Barcelona and Rome scientists shows the effect is not composition-specific, opening a route for quantum-effect control in electronics.

Summary

Researchers Probe Quantum

The quantum-metric signal in Sb2Te3 disappears above ~30 K as thermal scattering erodes spin polarization.
Sb2Te3’s Landé g-factor varies 2–30, with a best-fit near 10 that matches theory.
An in-plane magnetic field breaks time-reversal symmetry, yielding an antisymmetric sinusoidal second-harmonic response.
Raising the top-gate voltage shifts the Dirac cone and cuts the nonlinear signal ~45 %.
Researchers say higher-temperature operation is needed and link the results to a 2025 strontium-titanate experiment.

History

Historical Context

Building on Kane and Mele’s 2005 proposal of the quantum spin Hall effect, experimental work in 2007 confirmed two-dimensional topological insulators in HgTe quantum wells, and later three-dimensional bismuth-based compounds validated the broader topological-insulator framework. Today, researchers measuring Sb2Te3 extend this lineage, probing novel quantum-metric transport beyond conventional Berry-curvature descriptions.

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Geneva Researchers Measure

University of Geneva researchers measured the quantum metric in the three-dimensional topological insulator antimony-telluride (Sb2Te3).
Giacomo Sala and Andrea Caviglia led the experiment, published in *Nature Materials*.
The result confirms theory that the quantum metric shapes transport beyond Berry curvature and extends 2025 strontium-titanate/lanthanum-aluminate work.
Collaboration with Salerno, Barcelona and Rome scientists shows the effect is not composition-specific, opening a route for quantum-effect control in electronics.

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