Scientific publication report on self-assembled two-dimensional nanoscale strain networks formed within a single prismatic (H) polytype monolayer of TaS2 created in situ on the surface of an orthorhombic 1T-TaS2 single crystal by a low-temperature laser-induced polytype transformation.
COBISS.SI-ID: 32649511
Here we show that controlled optical or electromagnetic perturbations can lead to an amorphous metastable state of strongly correlated electrons in a quasi-two-dimensional dichalcogenide. Theoretical calculations confirm the correlations between localized charges to be crucial for the state’s unusual stability. The discovery belongs to the field of quantum physics and is fundamentally important as it opens up a new field. Understanding the phenomenon presents a new major challenge for today’s quantum physics.
COBISS.SI-ID: 32539431
The transition to a hidden metastable state in 1T-TaS2 is investigated in real time using coherent time-resolved femtosecond spectroscopy. Relying on spectral differences between phonon modes in the equilibrium states and in the metastable state, and temperature-tuning the metastable state lifetime, we perform stroboscopic measurements of the electronic response and switching of coherent oscillation frequency through the transition.
COBISS.SI-ID: 31265831
Here we study quantum interference arising from electron trajectories within equilateral triangular, monolayer quantum nanostructures, formed by femtosecond laser-induced quench through a first-order polytype structural transition in a layered transition-metal dichalcogenide material, TaS2. Experiments reveal scars in the quantum interference, as well as correlation effects that force electrons along commensurate paths. Quantum billiard, classical charged lattice gas Monte Carlo calculations and exact diagonalization methods are used to gain insight into the observed behaviour, and analyze the interplay between localized and itinerant states within such atomic-scale nanostructures.
COBISS.SI-ID: 47560195
By using time-resolved optical techniques and femtosecond-pulse-excited scanning tunneling microscopy (STM), we track the evolution of the metastable states in 1T-TaS2. We map out its temporal phase diagram using the photon density and temperature as control parameters on timescales ranging from 1 picosecond to1000 seconds. The introduction of a time-domain axis in the phase diagram enables us to follow the evolution of metastable emergent states created by different phase transition mechanisms on different timescales, thus enabling comparison with theoretical predictions of the phase diagram, and opening the way to understanding of the complex ordering processes in metastable materials.
COBISS.SI-ID: 62665219