Transport and response of quantum materials
Transport exposes how wavefunctions move charge, energy, and coherence through a material. We study the response of quantum systems across time and frequency, from the current immediately after a field is switched on to capacitance, optical weight, superfluid stiffness, and collective modes.
Geometry in motion
Band energies say which states are available. Quantum geometry determines how those states carry current and redistribute spectral weight. Our work connects the local structure of electronic wavefunctions to transport signals measured in time-domain, optical, capacitance, and superconducting experiments.
Selected papers
Quantum Geometry and the Hidden Scales in Materials
2026 · Nature Reviews Physics
This review shows how quantum geometry introduces intrinsic length, energy, and response scales that are invisible in the band dispersion alone. It gives the conceptual map for reading geometric effects across optical, dielectric, and many-body measurements.
Instantaneous Response and Quantum Geometry of Insulators
2025 · Proceedings of the National Academy of Sciences
Immediately after an electric field is switched on, the current probes the quantum metric before scattering and dissipation take over. This gives a direct bridge from wavefunction geometry to a time-resolved transport observable.
Framework to Measure Quantum Metric from Step Response
2025 · Physical Review Letters
A sudden drive turns the quantum metric into a measurable dynamical signal. The framework identifies which part of the early-time response is geometric and how it can be extracted without reconstructing the full wavefunction.
Quantum Geometry in Quantum Materials
2025 · npj Quantum Materials
Raquel’s review with Jiabin Yu, Andrei Bernevig, Enrico Rossi, Päivi Törmä, and Bohm-Jung Yang connects quantum geometry to optical response, Landau levels, fractional Chern phases, superfluid weight, spin stiffness, excitons, and electron-phonon coupling.
The Quantum Geometric Origin of Capacitance in Insulators
2024 · Nature Communications
Capacitance is not only an electrostatic property. In an insulator, the ability to polarize also records the spread and geometry of the occupied quantum states, turning a familiar response coefficient into a probe of wavefunction structure.
Geometric Stiffness in Interlayer Exciton Condensates
2024 · Physical Review Letters
In an interlayer exciton condensate, phase rigidity has a geometric contribution inherited from the underlying bands. The result links quantum metric to counterflow response and collective coherence in a directly testable setting.
