Optical coherent transients by laser frequency switching

Coherence phenomena such as photon echoes, free induction, and nutation effects are easily detected in molecular iodine using a frequency-switched tunable cw dye laser. This technique is generally applicable to atoms, molecules, and solids and offers unique ways for probing dynamic interactions in a selective manner. Elastic and inelastic collision mechanisms for I2 are examined independently and compared with theory. © 1976 The American Physical Society.