Commercial, table top ultrafast lasers can output incredibly short optical pulses, enabled by a technique called chirped pulse amplification, which received the 2018 Nobel Prize in Physics. In our lab, we routinely use optical pulses with durations of about 100 femotseconds - that is 10 quadrillionths of a second. Specialized labs around the world have achieved pulses 1000x smaller. One  key advantage of such short pulses is that they allow us to study ultrafast events in solids and materials. Think of a short optical pulse as the shutter speed on a camera: to capture something moving very quickly, your camera shutter speed must be very short, or else you will just get a blur across your photo. Electronic carriers - which drive high speed transistors, and high bandwidth diode lasers - move across small semiconductors and make electronic transitions on these ultrashort time scales. We use a technique called ultrafast pump-probe spectroscopy to measure the lifetime of carriers  in the electronic states of semiconductor materials. Understanding the physics of these processes guides us how to improve the material, and to engineer new materials. A second key advantage of short pulses is that they enable us to achieve very high peak powers and electric fields; the peak power increases directly with the pulse duration. These high peak powers can be used to generate a nonlinear optical response of materials.  See the below presentation for an introduction to chirped pulse amplification and ultrafast spectroscopy.

Cafe Scientifique presentation: Chirped Pulse Amplification, the 2018 Nobel Prize in Physics, and Ultrafast Spectroscopy