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Science & Technology => Outer Space => Topic started by: Jonnie Goodboy on December 26, 2012, 04:05:34 am



Title: Opening up the Radio-Sky. UK Man Develops Room Temperature MASER from eBay junk.
Post by: Jonnie Goodboy on December 26, 2012, 04:05:34 am
Using spare chemicals, a laser bought on eBay and angst from a late-night argument, BRITISH physicists have got the world's first room-temperature microwave laser (& µwave amplifier) working.

The full paper, 'Room-temperature solid-state maser', was published in Nature on 16 August 2012.
http://www.nature.com/news/microwave-laser-fulfills-60-years-of-promise-1.11199#/b1

http://www.youtube.com/watch?v=M4EQN6-EXHY


The achievement comes nearly 60 years after the first clunky versions of such devices were built, and could revolutionize communication and space exploration. The work is published in August, 2012 in Nature.

Conventional MASER technology works by amplifying microwaves using crystals such as ruby - this process is known as 'masing'. However, the MASER has had little technological impact compared to the LASER because getting it to work has always required extreme conditions that are difficult to produce; either extremely low pressures, supplied by special vacuum chambers and pumps, or freezing conditions at temperatures close to absolute zero (-273.15 °C), supplied by special refrigerators. To make matters worse, the application of strong magnetic fields has often also been necessary, requiring large magnets.

Now, the team from NPL and Imperial have demonstrated masing in a solid-state device working in air at room temperature with no applied magnetic field. This breakthrough means that the cost to manufacture and operate MASERs could be dramatically reduced, which could lead to them becoming as widely used as LASER technology.


Oxborrow enlisted two colleagues — materials scientists Jonathan Breeze and Neil Alford from Imperial College London — and got to work on testing this suggestion. He borrowed some spare pentacene from a lab at Imperial, and cooked it with another organic molecule known as p-terphenyl. The result was a pink crystal a few centimetres long.

(http://www.nature.com/polopoly_fs/7.5882.1345055477!/image/1.11199.jpg_gen/derivatives/landscape_300/1.11199.jpg)
Mark Oxborrow shows off the homemade kit for purifying p-terphenyl

Next, the team needed a powerful laser. Oxborrow located an old medical laser on eBay and drove to a warehouse in north London to pick it up. But the researchers were filled with doubts — the whole thing seemed too easy. Oxborrow admits that he was skittish about the experiment. "For about three days, I could have done it, but I didn't have the nerve to switch on that button," he says.


Title: Re: Opening up the Radio-Sky. UK Man Develops Room Temperature MASER from eBay junk.
Post by: Jonnie Goodboy on December 26, 2012, 11:33:23 am
Whilst PrisonPlanet is Busy Banning my comments, literally just now, (Amazing, What a Great Guy!) I received this message reply from Prof Mark in reply to a general question on the development of this field !!!

"
I am more than happy to talk with radio/astronomy enthusiasts about hardware, experiments and practical challenges. They often understand things better than the pros! I attach a copy of the Nature letter in case you have not managed to get your hands on a copy.

There are also an “intro” to the technology and a lecture (for a general non-specialist audience) on youtube that you can watch
:

http://www.youtube.com/watch?v=M4EQN6-EXHY

http://www.youtube.com/watch?v=yB975l-PEbM

Please note that, at present, the pentacene maser (as reported above) only amplifiers in the L-band at near 1.45 GHz (near the 21 cm hydrogen line), with a bandwidth of a few MHz, and in pulsed mode.  I am currently doing research towards improvements that avoid these limitations: CW operation, at other frequencies (UHF to C-band) and somewhat greater bandwidth –though still nowhere as broad as what GaAs or InP HEMT-based amplifiers offer."