When the continuous symmetry of a physical system is spontaneously broken, two types of
collective modes typically emerge: the amplitude and the phase modes of the order …

Quantum-mechanical phenomena underpin the behaviour of quantum materials at the
microscopic level. The description of several essential properties of these materials …

The coupling between superconductors and oscillation cycles of light pulses, ie, lightwave
engineering, is an emerging control concept for superconducting quantum electronics …

Light-induced supercurrents chart a path forward for the electromagnetic design of emergent
materials phases and collective modes for quantum engineering applications. However …

We report terahertz (THz) light-induced second harmonic generation, in superconductors
with inversion symmetry that forbid even-order nonlinearities. The THz second harmonic …

We theoretically study the low-energy electromagnetic response of Bardeen-Cooper-
Schrieffer–type superconductors focusing on propagating collective modes that are …

Recent findings of new Higgs modes in unconventional superconductors require a
classification and characterization of the modes allowed by nontrivial gap symmetry. Here …

Characterizing and controlling high-order correlation of quantum systems is key for
developing quantum devices and switching technologies. Although conventional static and …

Giant second-harmonic generation in the terahertz (THz) frequency range is observed in a
thin film of an s-wave superconductor NbN, where the time-reversal (T) and space-inversion …

In multiband superconductors, multiple collective modes exist associated with the multiple
order parameters. Oscillations of the amplitude and the relative phase of the order …