Broadband two-dimensional spectrochronography with ultrashort pulses in the mid-infrared

A novel, 2.6-to-10-??m wavelength-tunable laser source of sub-70-fs pulses is combined with mid-IR heterodyne detection to provide a versatile laser platform for broadband two-dimensional Fourier-transform infrared spectrochronog-raphy. The mid-infrared laser output serves as both a short-pulse driver and a broadband probe for time-resolved studies of ultrafast molecular coherence, population dynamics, and mul-timodal energy transfer in a vast class of complex molecular systems.