Advanced Light Source gets scientific program head

September 16, 1994

By Lynn Yarris, [email protected]

Neville Smith, 52, a leader in photoemission spectroscopy for 25 years with AT&T Bell Laboratories, has been appointed the first scientific program head of the Advanced Light Source. Smith was named to the position by LBL director Charles V. Shank, effective immediately. Phil Ross, a chemist with the Materials Sciences Division who had been acting ALS scientific advisor, has returned to his research.

Smith will supervise the ALS user program, chair the new Program Advisory Committee, act as the ALS scientific representative, and ensure that Light Source operations meet the scientific goals of all users, including industrial participants. Currently, he is developing the formal process by which independent investigators will be able to use the ALS.

A native of England with a Ph.D. in physics from Cambridge University, Smith came to the U.S. in 1966. After doing post-doctoral research at Stanford University under William Spicer, a pioneer in photoemission spectroscopy, he joined the staff at Bell Labs in Murray Hill, N.J.

Smith comes to LBL already quite familiar with the Light Source. In 1987 he was made a member of the ALS Users' Executive Committee and for the next six years, chaired the ALS Program Review Panel, which reviewed all the proposals to form participating research teams.

Smith takes his position at a time when the ALS scientific program he helped launch is beginning to produce results.

"The machine works even better than what was called for in its specifications and the high brightness of its beams is really paying off," he says. "Industrial users are finding out that we've got an instrument that is capable of solving many of their problems."

Prominent among these recent experimental results was a study by a research team from Uppsala, Sweden, using soft x-ray fluorescent spectroscopy (SXRFS) to investigate the structure of fullerene molecules (also known as buckyballs) with unprecedented resolution. A collaborative team from the universities of Tennessee and Tulane, working with an undulator beamline they share with IBM, also used SXRFS to study interfaces buried so far below sample surfaces as to be inaccessible to photoemission spectroscopy.

"We currently have in place three undulator and four bending magnet beamlines, and are planning for two wigglers and another undulator to be in place by 1996," says Smith. "That will leave us with four straight sections (the sections of the ALS storage ring that accommodate undulators or wigglers) unspoken for. Part of my job is to identify potential new user communities and make sure those communities know about the potential of the ALS."

Smith envisions a strong Life Sciences program for the ALS. Funding has already been procured for an x-ray crystallography beamline and laboratory support facilities, and for an x-ray microscope that would provide five times the resolution of optical microscopes for the study of biological materials in their natural aqueous environment. Partial funding has been obtained for an elliptical wiggler that would provide circularly polarized light. In addition to the study of the right-handed and left-handed properties of biological materials, this circularly polarized light could also be used to characterize magnetic properties in complex materials.

For his own research on the ALS, Smith is in the process of establishing an experimental program in spin-polarized photoemission spectroscopy. This process involves the analysis of the quantum mechanical property known as "spin" of electrons emitted from a material as a result of exposure to x-rays.

Under Smith's proposal, an elliptical wiggler beamline will be used to examine how photoelectron spin state relates to electronic structure at the surface of a sample material. This information in turn will be related to the material's magnetic properties. Among other applications, it should help researchers learn how to pack more bits of data onto the computer storage disks of the future.