Time-dependent (Figs 8 (a & c)) measurements used a high speed HgCdTe detector (Vigo PVI-3.4-1×1- TO39-NO WINDOW-35, 1ns rise time) for 3.1 µm and a high speed InGaAs detector (Thorlabs DET01CFC) for 1.5 µm.A 350 MHz digital oscilloscope (Agilent InfiniiVision DSO-X-3032A) and 6 GHz spectrum analyzer (Agilent CSA Spectrum Analyzer) were used for measurements.The spectral measurements in Fig. 8b, was used a liquid-nitrogen-cooled InAs detector (Electro-Optical Systems S-010-LN4).