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Solar pumped laser reaches 80W

A new report from Prof. Takashi Yabe: 100 W-class solar pumped laser for sustainable magnesium-hydrogen energy cycle, J. Appl. Phys. 104, 083104 (2008). They used a Fresnel lens (2×2 m, f=2000 mm) for collecting solar radiation, a Cr:Nd: YAG ceramic rod as gain medium, and get 80 W maximum laser power, corresponding to a 4.3% net conversion from solar light. That's really a cool result.

I always say to my colleagues that solar pumped laser is my dream research project, because then I can do experiments under sunshine instead of in a basement lab. ;)

Dr. Rüdiger Paschotta's books

Dr. Rüdiger Paschotta, who runs a consulting company after a successful academic career, just published another book: SPIE Field Guide to Laser Pulse Generation. His first book is SPIE Field Guide to Lasers.

Encyclopedia of Laser Physics and Technology, his notable and useful web project, also has a print version now.

He leads a very interesting career.

Active galactic nuclei with laser guide star adaptive optics

I found this presentation on Google Video: Active galactic nuclei with laser guide star adaptive optics. It is from the AAS 212th Meeting. The presenter is Claire Max.

Adaptive optics on the current generation of 8 - 10 meter telescopes yields spatial resolutions in the near-infrared comparable to those of Hubble at visible wavelengths. Laser guide stars are now making these high spatial resolutions available over a large fraction of the sky. I will describe several areas in which these advances are being applied to AGN science: 1) measurement of black hole masses in nearby galaxies from kinematics of stars and gas; 2) study of the spatial distribution of stellar populations and dust in galaxies at 0.5 < z < 1.5, and 3) tests of the relationship between galaxy mergers and AGN activity. I will conclude with a discussion of the planned Next Generation Adaptive Optics system at the W. M. Keck Observatory, outlining the expected improvements in AGN science with this new system.

A timelapse of the Paranal laser guide star


The authors of the time lapse movie are Stéphane Guisard, Valère Leroy and Jean Pajus. It is fun to see the PARSEC laser pointing to different directions of the universe over the night. I wonder what the night sky would look like in Hawaii, where there are several guide star lasers.

This is a time lapse movie made from individual images taken with a Canon 20Da camera and a 8mm lens. This accelerated movie shows a complete night at Paranal Observatory starting at sunset and finishing at dawn. That night, the Laser Guide Star Facility was in use and its yellow sodium Laser beam left its footprint on our movie. The laser beam creates a Laser Guide Star in the high atmosphere, 90 km above us. This 'bright' artificial star helps the adaptive optics system located in the main telescope, to measure and correct the distorsions of the images produced by the atmosphere, in real time and several hundreds of times per second.

The bright part of the Milky Way, containing the galactic center, is disappearing to the west on the left hand side of the movie. The Andromeda galaxy is visible also, as a diffused and elongated spot crossing the sky just above the domes. One can also see the Pleiades and "upside down" Orion constellation rising (remember this movie is done from the Southern hemisphere) together with the other half of our Milky Way . Finally the moon lightens the morning sky just before sunrise.

Narrow linewidth laser with fiber Raman amplification

We have a new publication online now: multiwatts narrow linewidth fiber Raman amplifiers. Basically, the paper shows fiber Raman amplifier can be used to amplify narrow linewidth laser to a useful power level, while linewidth keeping narrow. This would be a surprise to most laser researchers. In this specific report, we have obtained 4.8 W, ~10MHz 1178nm laser with 27dB gain and more than 10% efficiency.

OSA Podcast: Enhancing Your Career in Optics

An update from OSA Podcast, on career in Optics. Worth listening.

First Laser

May 16, 2008. Above is today's Google logo.

The first working laser was demonstrated on May 16, 1960 by Theodore Maiman at Hughes Research Laboratories.

According to Wikipedia.

Mitsubishi unveils laser TV

The hottest buzz right now in technology blogosphere is that Mitsubishi unveils Laser TV at a Consumer Electronics Show 2008 in Las Vegas.

Photo from PopSci

Nature Photonics Technology Focus: Fiber Lasers

January 2008 issue of Nature Photonics has a technology focus on fiber lasers. Some recent research highlights are presented, like report of millijoule femtosecond fiber laser from Jena University. Several people from companies (SPI Lasers, IPG Photonics, Koheras) are invited to write their perspective on fiber lasers. Prof.