The History of the X-ray Laser

The long and curious history of the X-ray laser began in an effort to expand the frontier of knowledge and culminated in one of the wildest schemes ever pursued by the United States government—the “Star Wars” missile defense initiative in the 1980s.

Jeff Hecht

Scatterings

Micro-harp resonates to sound out gases; imaging collagen fibers; a quantum stroboscope.

Yvonne Carts-Powell

Directly Pumped Silicon Lasers

Over the past two decades, researchers have tried mightily to enhance silicon’s ability to emit light. Yet electrically pumped silicon lasers remain tantalizingly out of reach. These authors describe how the approaches that have been tried so far might be successfully combined.

Jeffrey M. Shainline and Jimmy Xu

Electrically Pumped
Photonic Crystal Nanolasers

For years, the quantum optics community has been testing the limits on laser size: How small can you go? Thanks to advances in semiconductor crystal growth and fabrication techniques, the answer is now wavelength-scale.

H.-G. Park, M.-K. Seo, S.-H. Kim and Y.-H. Lee

Fiber Lasers and Their Coherent Beam Combination

With high efficiency and exceptional beam quality, fiber lasers hold great promise. The 1-µm wavelength makes it possible for them to replace both diode- and lamp-pumped Nd:YAG lasers in the micromachining, automotive and biomedical markets.

Q. Lou, J. Zhou, B. He and H. Zhao