Nanosecond time-resolved spectroscopy with a pulsed tunable dye laser and single photon time correlation

A technique is described for performing nanosecond time-resolved spectroscopy for situations of extremely low emission rates. The system utilizes a N(2) laser pumped tunable dye laser and single photon time correlation techniques. It is applicable where there is need for nanosecond time resolution on emission which is either long-lived or has extremely low quantum efficiency and especially where monochromatic excitation is required. The technique is applied to the relaxation between a pair of excited states of Tb(3+):Y(OH):(3), where 5-nsec temporal resolution with 2- cm(-1) spectral resolution is easily obtained.