Lee Sanghun, Kim Eunseo, Bang Junho, Park Jongho, Kim Changyoung, Wulferding Dirk, Cho Doohee
Department of Physics, Yonsei University, Seoul 03722, Republic of Korea.
Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea.
Nano Lett. 2023 Dec 13;23(23):11219-11225. doi: 10.1021/acs.nanolett.3c03721. Epub 2023 Nov 29.
Solids undergoing a transition from order to disorder experience a proliferation of topological defects. The melting process generates transient quantum states. However, their dynamic nature with a femtosecond lifetime hinders exploration with atomic precision. Here, we suggest an alternative approach to the dynamic melting process by focusing on the interface created by competing degenerate quantum states. We use a scanning tunneling microscope (STM) to visualize the unidirectional charge density wave (CDW) and its spatial progression ("static melting") across a twin domain boundary (TDB) in the layered material GdTe. Combining the STM with a spatial lock-in technique, we reveal that the order parameter amplitude attenuates with the formation of dislocations and thus two different unidirectional CDWs coexist near the TDB, reducing the CDW anisotropy. Notably, we discovered a correlation between this anisotropy and the CDW gap. Our study provides valuable insight into the behavior of topological defects and transient quantum states.
