Active control of quantum materials is highly desirable for a wide range of applications. Metastable hidden states, such as the one discovered a few years ago by researchers at the Department of complex matter at the Jožef Stefan Institute, offer completely new functionalities. However, the underlying mechanisms that lead to hidden states remains a largely open scientific topic. In a new study published on November 24 in Science Advances, prof. dr. Dragan Mihailović in collaboration with a group of researchers from Germany and USA, investigated coherent control of the transition to a metastable hidden quantum state in the quantum material 1T-TaS₂. Using time- and angle-resolved photoemission spectroscopy (trARPES), electronic and collective excitations during the transition to the hidden state were investigated in real time. Using laser excitation with time-controlled pulses, they managed to coherently control the transition to the hidden phase, thus revealing the importance of collective excitations which helped elucidate the mechanism for this interesting phenomenon.
You can read the article here: https://www.science.org/doi/10.1126/sciadv.adi4661