Electric-Field Driven Domain Reconfiguration in The Charge Density Wave 1T-TaS₂

Charge density wave (CDW) is ubiquitous in quantum materials. Under a minor electric field, CDWs fluctuate giving rise to increased electric conductivity long believed to arise from the depinning and sliding of CDWs. In real space, sliding of CDW will lead to the reconfiguration of CDW domains on the nano and mesoscale. Direct observation of sliding CDW is challenging. The nature of such reconfigurations, e.g., whether they are stochastic, as well as the relevant timescales, remains elusive.<br/><br/>We used X-ray Photon Correlation Spectroscopy (XPCS) for revealing E-field-driven domain reconfigurations in the canonical CDW material 1T-TaS₂. Combining in-situ XPCS studies with few-seconds counting time at the Advanced Photon Source (APS) and the 100 fs X-ray pulses at the MID endstation of the European XFEL, we show the CDW domain reconfigure above few microseconds and reaches ergodicity in domain configuration by seconds. These results shed light on the nature of the CDW fluctuation in 1T-TaS₂ as a stochastic process. Our results also provide quantitative measure of the depinning energy landscape in the material, which is critical to the macroscopic transport material property.