Stanford poised to address grand challenges in physics, national report indicates

By Brad Plummer

Science now stands at the edge of not only finally understanding the principles of quantum mechanics but utilizing those principles to benefit humankind, according to a report issued today by the National Academy of Sciences (NAS). Authored by a panel of top U.S. physicists, the report, titled AMO2010: Controlling the Quantum World, puts forth a vision for America's research future in the cutting-edge field of atomic, molecular and optical (AMO) science. The study details priorities for deepening our understanding of quantum mechanics and exploiting those findings.

The panel's aim is to guide research in the subatomic realm of the ultrasmall and ultrafast over the next 10 years. The AMO2010 report maps the future of quantum research in nontechnical language that underscores the fundamental impact this research could have on society in the next decade. By refining new tools and techniques for manipulating matter on the atomic scale and smaller, the United States and the world can look forward to continued and rapid advances in medicine, materials science, computing and national security.

"There's always a connection, particularly in this field, between fundamental questions and national need," says physicist Philip Bucksbaum of the Stanford Linear Accelerator Center (SLAC), who with former assistant director of the National Science Foundation Robert Eisenstein co-chaired the committee that issued the study. "The things that interest us in studying matter are always close to larger national priorities."

Bucksbaum directs the Photon Ultrafast Laser Science and Engineering (PULSE) center at SLAC, which is poised to address the physics challenges outlined in the study. Other Stanford researchers who contributed to AMO2010 include Professors Mark Kasevich (Department of Physics), Steven Kahn (Kavli Institute for Particle Physics and Cosmology) and Keith Hodgson (SLAC Photon Science Division).

The report is the result of 18 months of collaboration among a group of experts that included three Nobel laureates. AMO2010 is the second in a series of studies charting America's future in physics research. Last April, the NAS released a similar study detailing the challenges facing high-energy physics. Through periodic surveys such as these, the NAS seeks to guide national physics research by keeping lawmakers and the public informed about the common research challenges facing scientists.

Grand challenges

The AMO2010 report outlines a set of recommendations that promote science literacy in general and capitalize on the last century of discovery in quantum physics, focusing on six "grand challenges" facing researchers: What is the nature of physical law? What happens at the lowest temperatures in the universe? What happens at the highest? Can we control the inner workings of a molecule? How will we control and exploit the nanoworld? What is the future of quantum information science?

Besides the daunting challenge of working with matter on the atomic-length scale, where things are billionths of a meter or less, atomic events often happen on ultrafast time scalestrillionths of a second. Measuring the time it takes atoms to move within molecules or molecules to form and break bonds is technically demanding. To keep pace, researchers will need tools of increasing precision.

Lasers emerged from early discoveries in quantum mechanics, and they are now driving advances in the most successful branch of AMO sciencecooling matter to ultracold temperatures. Lasers have produced the coldest matter in the universe, called Bose-Einstein condensates, by selectively slowing down fast atoms until they all come nearly to rest. Advances such as these have led to vast improvements in precision timekeeping, such as the atomic clocks that are the backbone of the global positioning system. Ultracold states of matter also could play a role in quantum computers, in which individual atoms and photons are used to process information in ways conventional computers cannot. Quantum computers could enable researchers to tackle otherwise intractable problems in fields ranging from basic science to national security.

Stanford University has long played a leading role in technological advances in computing and laser research and, Bucksbaum says, will continue that tradition in AMO research with the impending completion of the world's first free-electron X-ray laser, the Linac Coherent Light Source (LCLS), at SLAC. The LCLS will produce a pulsed beam of X-rays a billion times brighter than any other source on earth. The LCLS beam will pulse 120 times a second, giving scientists a tool much like a camera's flash to take stop-motion pictures of atoms and molecules interacting with each other. Teams of scientists at SLAC are currently designing the first experiments to take place when the LCLS is switched on in 2009.

Stanford University operates SLAC for the U.S. Department of Energy. The National Academy of Sciences AMO2010 report was supported by grants from the U.S. Department of Energy and the National Science Foundation.