Extended Data Fig. 4: Temperature-dependent phonon oscillation decay.
From: Terahertz phonon engineering with van der Waals heterostructures
Phonon oscillations of device 3 at 77 K (a, b) and at 300 K (c, d) with similar pump fluences (300-400 μJ/cm2, lower than the saturation regime). Hann filters are used to remove the d.c. component. Note that the absolute pump fluences cannot be directly compared due to the different local field strengths at the FLG location at these two temperatures. The phonon amplitude lifetimes are calculated by the procedure described in section 4 of Supplementary Information.