Why the laser can refrigeration

Source：中国激光网   Time：2016-04-02   Edit：SunyLaser

      As early as 1985, Chinese American physicist Zhu Diwen successfully used the light to freeze the atoms, which won the 1997 Nobel prize in physics.
Why is the laser cooling? It turned out that the atoms of the object are always doing the irregular movement, which in fact is that the temperature of the object of the heat movement, that is, the more intense the atomic motion, the higher the temperature of the object, and vice versa, the lower the temperature. So, as long as the atomic velocity is reduced, the temperature of the object can be reduced. The principle of the emblem is to use a large number of photons to hinder the movement of atoms, so that it can slow down, thereby reducing the temperature of the object.
The velocity of an object's atomic motion is usually about 500 meters per second. For a long time, scientists have been looking for ways to keep atoms relatively static. Zhu Diwen uses three beams of mutually perpendicular to the laser, from all aspects of the atomic radiation, so that the atom trapped in the ocean, the movement continues to be hindered and slow down. This kind of effect of the laser is called "optical viscose" ". In the experiment, the atoms that are "stuck" can be reduced to an almost absolute zero.