Editing Time-resolved spectroscopy (section)

==Other multiple-pulse techniques==

Transient spectroscopy as discussed above is a technique that involves two pulses. There are many more techniques that employ two or more pulses, such as:
* Photon echoes.
* [[Four-wave mixing]] (involves three laser pulses)
* fifth-order experiments (involves four excitation pulses and a probe pulse)

The interpretation of experimental data from these techniques is usually much more complicated than in transient-absorption spectroscopy.

[[Nuclear magnetic resonance]] and [[electron spin resonance]] are often implemented with multiple-pulse techniques, though with radio waves and micro waves instead of visible light.