Nowadays, people and companies want to try to make smaller and smaller integrated circuits. In order to do this, low-power optical devices, like lasers, are needed. The question is how small can we make a laser? The answer is quite small - only two atoms are necessary. As you get smaller, things get fuzzy and people tend to disagree about what defines a laser. Gain narrowing is a term that refers to the fact that the bandwidth of light can be reduced to a point where the frequency only allows one color in the light spectrum, such as blue for a DVD player or red in other devices. When you put little energy into the system, only one color survives, Researchers explain, and this is the very thing we looked for in our system. We found that two atoms together can do the same thing that one ion with a cavity and mirrors can do. One atom is pumped, and at least one other atom nearby provides optical feedback. It is possible to introduce more atoms into the clustered system, and the team from The Netherlands posits clusters with up to five atoms in their Letter. The more atoms we have, the better the effect, Researcher say, but the fact remains that you only need one other atom besides the one that is pumped.
Source: physorg.comAdded: 26 March 2007