Experimental realization of coherent THz emission from MXenes

Establish the experimental realization of coherent terahertz emission from MXenes under engineered optical excitation, thereby testing the predicted correspondence between transient microscopic photocurrents and emitted terahertz radiation.

Background

The paper develops a density-matrix and non-secular Redfield framework for predicting coherent terahertz emission from MXenes driven by engineered multicolor femtosecond waveforms. The framework connects nonequilibrium carrier populations, interband quantum coherences, transient photocurrents, and emitted terahertz fields.

Experimental coherent terahertz emission has been demonstrated in related two-dimensional quantum materials, including graphene, layered transition-metal dichalcogenides, and Weyl semimetals. However, the paper identifies the corresponding experimental realization in MXenes under engineered excitation as unresolved, leaving a direct experimental test of the theoretical predictions outstanding.