Electronic phases in quantum materials are often governed by nanoscale inhomogeneity, where local order develops within spatially confined regions or puddles. A prominent example is an incommensurate charge-density-wave (I-CDW) that comprises locally commensurate domains. In 2H-NbSe2, such an I-CDW state persists alongside lattice anharmonicity and superconductivity, raising fundamental questions about the dynamical stabilization of CDW order in puddles. Here, we probe the puddle-dynamics in 2H-NbSe2. Raman scattering reveals a strong Fano-coupling between the interlayer shear vibration and the CDW amplitude mode. Time-resolved reflectivity measurement shows a low-frequency ~0.15 THz coherent overdamped oscillation onsetting within the CDW regime at ~17 K, pointing towards a so far unexplored transition. This we identify as a Fano-coupled phonon-CDW hybrid emerging from the collective dynamics of CDW puddles. These dynamics highlight how lattice pinning and electronic correlations in layered materials affect the CDW order, which is crucial for the design of novel Van der Waals devices.
@article{arxiv.2603.03980,
title = {Dynamics of Charge-Density-Wave puddles in 2$H$-NbSe$_2$},
author = {Shreya Kumbhakar and Marina Esposito and Anjan Kumar N M and Tommaso Confalone and Liwen Feng and Rafiqul Alam and Flavia Lo Sardo and Davide Masarotti and Francesco Tafuri and Thomas Böhm and Mahmoud Abdel-Hafiez and Sushmita Chandra and Claudia Felser and Kornelius Nielsch and Nicola Poccia and Stefan Kaiser and Golam Haider},
journal= {arXiv preprint arXiv:2603.03980},
year = {2026}
}