UMich's Optical Resonator Can Create Ultraviolet Beam Economically

In science, the type of light used is more often #-Link-Snipped-#, infrared or the #-Link-Snipped-#. However it was somehow difficult to produce an ultraviolet light i.e. light of shorter wavelength. Einstein had long proposed that the efficiency of the light produced will decrease as you move from green to blue. There is also a reason for this phenomenon which this great scientist researched upon. In other words, a green LASER producing object does not actually #-Link-Snipped-#. It is basically a light of higher wavelength with its wavelength decreased subsequently.

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Image Credit: In the setup for this experiment, a telecommunication-compatible infrared beam is coupled to the whispering-gallery resonator through a diamond prism and the generated near-infrared, visible, and ultraviolet light are collected by a multi-mode fiber. Image Credit: Mona Jarrahi

Playing with light of course has been a favorite past-time of opticians, this time researchers from University of Michigan have found out a better way of producing ultraviolet beams. The research was performed under the guidance of Mona Jarrahi and Tal Carmon, both asst. professors at Dept. Of Electrical and Computer Science.

In the experiment, Research team devised a way of converting Infrared Light to Ultraviolet beam. This was done by using a specially designed optical resonator. The disc shaped resonator was so made as to maximize the voltage gain when an infrared signal was obtained from a usual telecommunication #-Link-Snipped-#. The disc helped them to convert this low energy signal to a high efficiency and high energy ultraviolet light.

Practically speaking, as we are using simple components like a common telecommunication laser, the overall cost of producing the ultraviolet light comes down. This will introduce an interesting way in which UV beam is used. No doubt, latest findings will be useful for the existing applications of the UV rays like chemical detection, spectroscopy, Lithography and others, the research by Jarrahi and Carmon is bound to open new avenues for the use of UV where it was earlier seen as more complicated.

This is feasible because we can #-Link-Snipped-# just by using a specially designed optical resonator. But one thing is for sure, the shape of the resonator will matter a lot. In the present experiment, after keeping the wavelength could be reduced to obtain the fourth Harmonic of the input signal. Hence design actually matters the final output.

You can read more about the research of University of Michigan team in the current issue of #-Link-Snipped-# titled #-Link-Snipped-#.