Saturday, June 07, 2014
A new way to make laser-like beams using 250x less power
Polariton is a combination of a photon or light particle and an exciton – an electron-hole pair. The electron is negatively charged and the hole is technically the absence of an electron, but it behaves as if it were positively charged. Excitons will only fuse with light particles under just the right conditions. Too much light or electrical current will cause the excitons to break down too early. But with just enough, polaritons will form and then bounce around the system until they come to rest at their lowest energy level in what Bhattacharya describes as a coherent pool. There, the polaritons decay and in the process, release a beam of single-colored light.
The beam they demonstrated was ultraviolet and very low power – less than a millionth of a watt. For context, the laser in a CD player is about one-thousandth of a watt.
99% BAD HARDWARE WEEK: What does mean room temperature? If it is -40C than it is deep freeze room temperature :)
Another progress direction is to demonstrate this effect in silicon basic silicon nano structure. It is intristically worse than GaN, but 250 times lower power consumption will give it wings.