Featured Research

from universities, journals, and other organizations

A smarter way to make ultraviolet light beams

Date:
December 1, 2011
Source:
University of Michigan
Summary:
Existing coherent ultraviolet light sources are power hungry, bulky and expensive. Researchers have found a better way to build compact ultraviolet sources with low power consumption that could improve information storage, microscopy and chemical analysis.

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.
Credit: Photo courtesy of Mona Jarrahi

Existing coherent ultraviolet light sources are power hungry, bulky and expensive. University of Michigan researchers have found a better way to build compact ultraviolet sources with low power consumption that could improve information storage, microscopy and chemical analysis.

A paper on the research is newly published in Optics Express. The research was led by Mona Jarrahi and Tal Carmon, assistant professors in the Department of Electrical Engineering and Computer Science. The experiment was performed by Jeremy Moore and Matthew Tomes, both graduate students in the same department.

The researchers have optimized a type of optical resonator to take an infrared signal from relatively cheap telecommunication-compatible lasers and, using a low-power, nonlinear process, boost it to a higher-energy ultraviolet beam.

Their optical resonator is a millimeter-scale disk with a precisely engineered shape and smooth surface polishing to encourage the input beam to gain power as it circulates inside the resonator.

"We optimized the structure to achieve high gain over a broad range of optical wavelengths," Jarrahi said. "This allows us to make low-cost, wavelength-tunable ultraviolet sources using low-infrared power levels."

The researchers used their resonator to generate the fourth harmonic of the infrared beam they started with.

Like the harmonic distortions you get from new sound frequencies when you crank up a loudspeaker, engineers can generate harmonics of light by using the right materials. By pushing light beams through a nonlinear medium, they can coax out offshoot beams that are double, or in this case, quadruple the frequency and energy of the input beam, and one-quarter of the original wavelength.

Lasers get progressively more difficult to generate and more inefficient, as engineers aim for shorter wavelengths, the researchers said.

"As we go from green to blue, the efficiency of the laser goes down. Going to UV lasers is even harder," Jarrahi said. "This principle was first suggested by Einstein and is the reason why green laser pointers do not actually contain a green laser. It is actually a red laser and its wavelength is divided by two to become green light."

Ultraviolet light sources have applications in chemical detection, crisper medical imaging and finer lithography for more sophisticated integrated circuits and greater computer memory capacity.

The paper is titled "Continuous-wave ultraviolet emission through fourth-harmonic generation in a whispering-gallery resonator." The research was funded by the National Science Foundation and the Air Force Office of Scientific Research.



Story Source:

The above story is based on materials provided by University of Michigan. Note: Materials may be edited for content and length.


Cite This Page:

University of Michigan. "A smarter way to make ultraviolet light beams." ScienceDaily. ScienceDaily, 1 December 2011. <www.sciencedaily.com/releases/2011/11/111129162902.htm>.
University of Michigan. (2011, December 1). A smarter way to make ultraviolet light beams. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2011/11/111129162902.htm
University of Michigan. "A smarter way to make ultraviolet light beams." ScienceDaily. www.sciencedaily.com/releases/2011/11/111129162902.htm (accessed September 2, 2014).

Share This




More Matter & Energy News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Australian Airlines Relax Phone Ban Too

Australian Airlines Relax Phone Ban Too

Reuters - Business Video Online (Aug. 26, 2014) Qantas and Virgin say passengers can use their smartphones and tablets throughout flights after a regulator relaxed a ban on electronic devices during take-off and landing. As Hayley Platt reports the move comes as the two domestic rivals are expected to post annual net losses later this week. Video provided by Reuters
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Chinese Researchers Might Be Creating Supersonic Submarine

Chinese Researchers Might Be Creating Supersonic Submarine

Newsy (Aug. 26, 2014) Chinese researchers have expanded on Cold War-era tech and are closer to building a submarine that could reach the speed of sound. Video provided by Newsy
Powered by NewsLook.com
Breakingviews: India Coal Strained by Supreme Court Ruling

Breakingviews: India Coal Strained by Supreme Court Ruling

Reuters - Business Video Online (Aug. 26, 2014) An acute coal shortage is likely to be aggravated as India's supreme court declared government coal allocations illegal, says Breakingviews' Peter Thal Larsen. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins