What is laser cooling?
Laser cooling is a method of slowing atoms, so cooling is with lasers. We usually consider lasers to heat things and certainly do it on macroscopic standards, but for individual atoms or small groups of atoms can be used for cooling. The coldest temperatures ever generated, less than half a billion Kelvin (0.5 nanokellvines) were achieved by a combination of laser cooling and evaporation cooling. These temperatures are achieved by a small amount of diffusion gases. As long as the speed of the atom is greater than the photon emissions, the total speed will be reduced. If you floated on a hovering with movement, they moved at a significant speed in one direction and accidentally threw the metal balls from the hovering seas of the reverse effect of the ball throwing. This is how the laser cooling works.
Laser cooling is selectively targeting atoms moving in certain directions and at certain speeds in the gas. OnBy tuning the light at a specific frequency, just below the resonant frequency for the substance, the laser traps only target the atoms that are heading towards it. This is due to a doppler effect - when the atom moves towards the source laser, the frequency of light increases from the atom point of view. This is the same reason why the sound frequency changes, as the train increases around the stationary observer - the relative speed between the source and the object manipulates the apparent frequency. In order not to move atoms at this threshold, they are transparent to the laser and are therefore not affected.
When the apparent frequency of light due to certain atoms in laser C Cooling trap is true, the atom absorbs incoming photons, is temporarily more energy and then releases a photon. Atoms moving in a certain direction over the threshold is selected by a laser cooling device. The arrangement of lasers in a three -dimensional matrix surrounding the diffusion gas may be atomic speed in all three levels of freeThose damaged, leading to less atomic movement and therefore to a lower temperature. The gas must be diffuse to ensure that photons are not reabsorbed by neighboring atoms. Laser frequency manipulation may also be slowly, as it may require several phases of cooling to reduce the gas to the desired temperature. Do it carefully and maybe you will get the research grant you always wanted.