5 papers
Discovery of Light-induced Metastable Martensitic Anomaly Controlled by Single-Cycle Terahertz Pulses
X. Yang, B. Song, C. Vaswani +9
We report on an ultrafast photoinduced phase transition with a strikingly long-lived Martensitic anomaly driven by above-threshold single-cycle terahertz (THz) pulses in NbSn.…
Coherent Band-Edge Oscillations and Dynamic LO Phonon Mode Splitting as Evidence for Polaronic Coupling in Perovskites
Z. Liu, C. Vaswani, L. Luo +12
The coherence of collective modes, such as phonons, and their modulation of the electronic states are long sought in complex systems, which is a cross-cutting issue in photovoltaic…
Light-Driven Raman Coherence as a Non-Thermal Route to Ultrafast Topology Switching
C. Vaswani, L. -L. Wang, D. H. Mudiyanselage +14
A grand challenge underlies the entire field of topology-enabled quantum logic and information science: how to establish topological control principles driven by quantum coherence…
Discovery of Terahertz Second Harmonic Generation from Lightwave Acceleration of Symmetry--Breaking Nonlinear Supercurrents
C. Vaswani, C. Sundahl, M. Mootz +11
We report terahertz (THz) second harmonic generation (SHG) in superconductors (SC) with inversion symmetric equilibrium states that forbid even-order nonlinearities. Such SHG signa…
Ultrafast Control of Excitonic Rashba Fine Structure by Phonon Coherences in a Metal Halide Perovskite CHNHPbI
Z. Liu, C. Vaswani, X. Yang +14
We discover hidden Rashba fine structure in CHNHPbI and demonstrate its quantum control by vibrational coherence through symmetry-selective vibronic (electron-phonon) c…