Medal Winner Talks Lasers

2009 has been a special year of advancements for lasers, and by October 2010 the power of the sun could be ever-so-briefly generated in the laboratory. Those are some of the points made during an address Monday by renowned laser scientist Robert L. Byer during the awards ceremony at Frontiers in Optics 2009.

Robert L. Byer speaks during the awards ceremony of the Optical Society's Frontiers in Optics 2009. Byer was awarded the society's highest honor, the Frederic Ives Medal/Jarus W. Quinn Endowment. (Photonics Media photo by Melinda Rose)

Byer, currently the William R. Kenan Jr. Professor of Applied Physics, was the recipient of the Optical Society's highest honor, the Frederic Ives Medal/Jarus W. Quinn Prize for his pioneering contributions to optical science. He has taught classes on lasers and nonlinear optics at Stanford University since 1969 and holds more than 50 patents related to lasers and nonlinear optics.

His extraordinary contributions to laser science cited by OSA include demonstration of the first tunable visible parametric oscillator, the development of the Q-switched unstable resonator Nd:YAG laser, remote sensing using tunable infrared sources, and precision spectroscopy using coherent anti-Stokes Raman scattering (CARS). Byer's ongoing research includes development of nonlinear optical materials and laser diode-pumped solid-state laser sources for applications to gravitational wave detection and to laser particle acceleration.

In his presentation, "Surfing Lightwaves: Meeting the Challenges of the 21st Century," he provided an overview of some of this year's laser milestones, such as Northrop Grumman Space Technology's announcement that it had produced the most powerful light ray yet created by an electric laser, measured at more than 105 kW and continuously operated it for five minutes; and the Linac Coherent Light Source at SLAC National Accelerator Lab at Stanford, the world's first hard x-ray free-electron laser (FEL), producing its first laser light in April.

Byer talked about arriving at Spectra Physics early in his career and finding the entrance deserted. He soon found out that, just then, "Earl Bell had just operated the first ion laser that generated orange light." He quickly joined the company to work with Bell, before moving into academia at Stanford.

Byer co-founded Quanta Ray Inc. in 1975 and helped develop the Q-switched unstable resonator Nd:YAG laser.

"My optimistic projection in 1975 was that the total market was about 75 lasers. Some 10,000 have been sold to date," Byer said.

He talked about developing an early modern version of a diode-pumped solid-state laser (DPSSL) that had 2 mW of output power, and how those lasers today are producing 100 kW of output power.

An immense slab of "continuous melt" processed neodymium-doped laser glass (Nd:Glass) used by the National Ignition Facility. (Photo: National Ignition Facility )

A key innovation was progress made in laser diodes, which are the most efficient way to convert electricity into coherent light. Other innovations include Nd:YAG and Nd:Glass lasers, and more recently edge-pumped, conduction-cooled slab lasers and polycrystalline ceramic lasers.

Byer estimated that there will be 1-MW slab laser MOPA (master oscillator power amplifier) by 2015. Lasers with higher output power -- megawatt lasers -- will be needed for applications such as laser fusion energy, and more powerful lasers have been driven by new technologies.

Byer discussed the work of accelerator labs such as SLAC and progress toward a tabletop coherent x-ray source, with the path toward tabletop systems based on the development of a mode-locked laser driven dielectric structure for FEL. The dielectric structures replace the traditional magnet and allow laser accelerators to operate at accelerating gradients of 1GeV/meter.

The challenges toward that goal are significant, he said, and would mean "inventing a new kind of laser and using it to illuminate photonic bandgap structures."

He estimated that "We should see the sun for a 10-picosecond duration by October 2010 in the laboratory."

For more information, visit: www.frontiersinoptics.com

Melinda Rose
Senior Editor

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