2025/09/11 by Dahal, Sajal, Viktor Krapivin, Miller, Alex H. +23
Chemistry · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Semiconductor Quantum Structures and Devices #Spectroscopy and Laser Applications #Statistical Mechanics (cond-mat.stat-mech) #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2509.09819
openalex publication_date 2025/09/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In phase transitions, mesoscale structures such as topological defects, vortex strings, and domain walls control the path towards equilibrium, and thus the functional properties of many active devices. In photoinduced phase transitions driven by femtosecond laser excitation, the temporal (pulse duration) and spatial (penetration depth) structure of the optical excitation present opportunities for control and creating structures with unique topologies. By performing time-resolved optical pump, x-ray probe experiments on the CDW system Pd-intercalated ErTe3, we gain access to the nanoscale dynamics of the mesoscale topological features (vortex strings) produced after a quench, which have a different apparent dimensionality than the topological defects predicted from the bulk system. We show that these vortex strings persist for much longer than the electronic recovery time. The critical exponent obtained from power-law scaling of the intensity as a function of wavevector shows a reduction in the effective dimensionality of the topological defects in the system, corroborated by time-dependent Ginzburg-Landau simulations. Our results demonstrate a novel pathway to use light to control the dimensionality and orientation of topological defects in quantum materials, which could be used to stabilize competing quantum states.