Laser cooling is a technique that uses light to cool atoms to a very low temperature. It was simultaneously propose by Wineland and Dehmelt and by Theodor W. Hänsch and Arthur Leonard Schawlow in 1975, and first demonstrated by Letokhov, Minogin and Pavlik in 1976. One conceptually simple form of laser cooling is referred to as optical molasses, since the dissipative optical force resembles the viscous drag on a body moving through molasses. Steven Chu, Claude Cohen-Tannoudji and William D. Phillips were awarded the 1997 Nobel Prize in Physics for their work in laser cooling.