The world's largest physics meeting

The APS March Meeting is traditionally a showcase for important fundamental physics and also the kind of practical research that shows up---five, ten, twenty years later---in the productive labor-saving devices we take for granted, technology such as the high-speed, high-density microchips in computers; superconducting components in medical imaging and wireless communications; quantum-well lasers in CD players and grocery scanners; and in sensitive detectors of aerosols and antigens.

This confluence of good physics and handy technology is reflected in the roll of March meeting press conference topics of recent years, including spintronics, carbon nanotubes, MEMS machines-on-a-chip, arrays of micromirrors for steering billions of phone calls, and DNA-based circuitry. These subjects are now or soon will be making their way into the marketplace. What next? Perhaps atomtronics, microfluidics, and Cooper-pair qubits. Please have a look below at our list of prospective highlights from the Indianapolis meeting.

WEBSITE AND PRESSROOM
The March Meeting website, http://www.aps.org/meet/MAR02/baps/ (click on "epitome" to view the sessions), offers a quick way to view hotel and travel information and all the abstracts. Complimentary press registration will allow science writers to attend all scientific sessions. If you wish to come, please fill out and return the form at the end of this release. Here is information relating to the press operations at the meeting:

---The meeting pressroom will be located in the Indianapolis Convention Center, room 114

---Press conferences will take place in the Convention Center, room 113

---Pressroom hours: Mon-Thu (March 18-21) 7:30 AM to 5 PM (12 PM close on 3/21).

---Pressroom phone numbers: 317-262-1590, 1610, 1558, 1490

-Pressroom fax number: 317-262-1678

---Virtual pressroom will be located at http://www.aps.org/meet/MAR02/baps/vpr/

---Breakfast and lunch food will be available in the pressroom from Monday-Thursday (breakfast only on Thursday).

---A press conference schedule will be issued in early March.

SOME EXPECTED HIGHLIGHTS OF THE MEETING

BOSE-EINSTEIN TECHNOLOGY
Bose-Einstein-condensed (BEC) atoms are chilled in laser light and at nanokelvin temperatures fall into a remarkable collective quantum state. For their early BEC work Eric Cornell, Wolfgang Ketterle, and Carl Wieman won the Nobel Prize in 2001, and at the meeting Wieman and Ketterle will be reporting (session J3, March 19) on their very latest efforts in this fast-moving subject. Other sessions (L6 and M3, Mar 20) demonstrate that notion that BEC might, by virtue of the fact that they can be produced and manipulated in microchips, also serve as the working substance in practical devices of unprecedented precision, in accelerometry, holography, timekeeping, and data crunching.

SWEET SMELL OF SUCCESS
Basic physics research has yielded numerous breakthrough technologies that have revolutionized the modern world around the globe and provided substantial economic benefit in the process. Speakers at a Wednesday morning session will describe several examples of such industrial success stories. For example, the Global Positioning System (GPS) has given rise a host of commercial consumer applications that generate billions of dollars each year, and is changing the way we determine where we are, as well as revolutionizing many fields of scientific research. Other speakers will discuss the economic impact of liquid crystal displays, optical fibers for telecommunications, automotive emissions control and physics applied to oil and gas exploration. (Session L7, March 20)

WILL LED's INHERIT THE EARTH?
Chris Van de Walle of the Palo Alto Research Center will deliver the prestigious Adler lecture. He is being recognized for work in a number of areas important for the application of condensed matter physics to electronic devices. One area is the role of hydrogen atoms used to neutralize ("passivate") undesirable effects of defects (such as reducing conductivity) in semiconductors. An example of Van de Walle's current work along this line is the effort to improve the efficiency of fuel cells by developing membranes which allow the movement of hydrogen atoms (or, to be exact, naked protons) but not any other particles, such as oxygen atoms. Van de Walle will also speak about the recent revival of interest in zinc oxide for use in blue-light-emitting diodes. Gallium nitride LEDs, owing to their much lower power consumption and their longevity, are already replacing light bulbs in a number of places, such as traffic, dashboard, and brake lights, and now that red, green, and blue light is available from LEDs (adding up to the equivalent of white light) solid-state illumination could eventually replace cumbersome bulbs in many home and business settings. Zinc oxide LEDs might be even more efficient and cheap and GaN since, for one thing, ZnO, unlike GaN, can be made in bulk crystals. (Session D6, Mar 18)

FUEL CELLS: NOT JUST FOR HYDROGEN ANYMORE
The Bush Administration recently announced the formation of Freedom CAR, a collaboration with major automakers to develop hydrogen fuel cells as a viable alternative technology for powering automobiles. Essentially, hydrogen fuel cells are devices that would convert hydrogen and oxygen cleanly and efficiently into electricity and heat. However, one major hurdle to this technology is the hydrogen fuel itself: pure hydrogen requires energy to produce, and once produced, it is hard to distribute, and exists in a bulky, inefficient gaseous form. Therefore, much interest exists in using other fuels, such as readily available hydrocarbons, in these devices. Raymond Gorte of the University of Pennsylvania will discuss a "solid-oxide" fuel cell design which can produce power from hydrocarbons, including readily available gasoline and diesel fuels. He will describe recent developments on the fabrication and use of this new type of fuel cell. (J7.1, Mar 19)

TERAHERTZ IMAGING: A NEW INSPECTION TECHNOLOGY
Physicists are still discovering useful regions in the rainbow spectrum of electromagnetic radiation. One such region is the realm of terahertz radiation, electromagnetic radiation corresponding to far-infrared light. Terahertz radiation is transparent to many packaging materials, making it attractive for product inspection, quality control, and detection of explosives, including plastic ones. It's very sensitive to water, making it useful for environmental monitoring. It also can produce images with details smaller than a millimeter. Daniel Mittleman of Rice University kicks off a focus session on terahertz technology (M8, March 20, 11 AM). Irfan Siddiqi of Yale will discuss experimental results on a device for "terahertz astronomy," which would make astronomical observations in the far-infrared region, where optical and radio astronomy techniques often falter. THz astronomy is especially promising for watching the birth of stars in molecular clouds. R. Koehler of NEST-INFM in Italy and his colleagues will report on a quantum cascade laser that emits radiation at 4.4 THz. Xiaogang Bai of the University of Michigan will present a quantum-well-based detector of terahertz phonons. Francisco Claro of the Catholic University of Chile discusses a molecular electronics device that may potentially act as a terahertz pulse detector.

TRAFFICKING IN COMPLEXITY
The powerful mathematical and statistical techniques of physics can be applied to many everyday situations. A session entitled "Coping with Complexity" covers advances in applying physics to such diverse areas as automobile traffic, drug design, finance, engineering design, and voting. Michael Schreckenberg of the University of Duisburg in Germany will describe the advent of new, more sophisticated traffic physics models that can now take into account certain aspects of a driver's behavior. Such models can help to explain more complex traffic patterns than previously possible. Detailing math- and physics-minded investigations into voting and other social decision making processes, Thad Brown of the Institute of Physical Sciences in Alexandria, Virginia will describe recent studies such as the effects of chaos on the outcomes of successive elections. In an earlier finding, Brown and a colleague showed that group decisions can be mathematically unpredictable even if the group has completely explicit decision making rules and members with unchanging opinions. (Session U7, Thursday, March 21)

DIAMAGNETIC LEVITATION: NOVEL APPLICATIONS
You don't need to be Harry Potter to levitate a frog, or any other living thing. Faster than Harry can say "Wingardium Leviosa," a very powerful magnet can do the same trick. That's because the water, protein, and DNA in living things are weakly diamagnetic, meaning that they produce a weak opposing magnetic field to any magnetic field applied to it. The stronger the applied field, the stronger the effect. The frog experiments, first reported in 1997, indeed used very powerful electromagnets. However, even a weak diamagnetic effect, generated by ordinary permanent magnets at room temperature, can levitate small objects, a feat first demonstrated in 1939. As Ron Pelrine of SRI International will explain, this low-cost capability opens many possibilities for practical applications. Ultra-sensitive tiltmeters, accelerometers, and flowmeters are among the prototype devices already built to take advantage of this phenomenon. Many possibilities exist, Pelrine says, for exploiting diamagnetic levitation in micro- and nano-scale devices, where smaller magnetic forces are required. However, diamagnetic applications are not restricted to the small scale; a recent experiment levitated a mass of over 20 pounds. (S6.003, March 21)

FROM POLYMER MATS TO DNA LOADS
In his lecture for the 2002 APS Polymer Physics Prize, Thomas Witten of the University of Chicago will describe his work (with Jacob Klein of Oxford University/Weizmann Institute and Uri Raviv of Weizmann) on polymer mats, which are polymers compressed after being adsorbed to a surface. Polymer mats have potential uses (for example, in stabilizing surfaces and reducing frictional forces) and continue to reveal surprises. Witten will report evidence that the polymers in such a mat paradoxically adopt stretched configurations, despite the compressive forces that produced them. John Marko of the University of Illinois at Chicago will describe progress made over the last 10 years in studying the physical properties of single DNA molecules using micromanipulation techniques. He will also discuss how his lab has started to study whole chromosomes from cells with such techniques. His work shows that the DNA molecule itself is the load-bearing element of the chromosome, which contains various proteins in addition to DNA. In efforts to develop simple and efficient mixing techniques for lab-on-a-chip devices, Armand Ajdari of ESPCI in Paris will discuss a technique that harnesses the phenomenon of chaos for mixing streams of fluids. The technique employs a simple-to-fabricate structure containing microscopic channels with bas-relief patterns, essentially sculpted features on a flat surface. (Session F2, March 19)

GETTING SEMICONDUCTORS TO COOPERATE
One of the most important interfaces in solid state physics is the place where silicon, arguably the best studied inorganic material in the world, comes up against other semiconducting layers, especially gallium-arsenide. The trouble is the mismatch in the atomic lattices of the two substances; it's like trying to put square pegs into round holes. Scientists at Motorola (Jamal Ramdani, paper M7-1, Mar 20) have addressed this problem by introducing a SrTiO3 buffer layer, allowing light-emitting GaAs to be laid down on a Si substrate.

HELIUM IN AEROGEL
Douglas Osheroff of Stanford got a Nobel Prize for observing how helium-3 becomes superfluid at a temperature of .0027 K. Since then scientists have sought to understand the mysteries of liquid He-3, which exists in not one but three superfluid phases, which have different magnetic and mechanical properties. One approach is to insert liquid helium into aerogel, that airy material hardly denser than air. The microscopic filaments of aerogel are supposed to act like one-dimensional impurities (rather than the usual point defects), and this acts to disrupt the process by which He-3 atoms pair up in the act of becoming superfluid. Osheroff will report (paper U1-4, Mar 21) the first observation of a transition between the A and B phases of liquid helium-3 in aerogel.

IT'S A SMALL WORLD AFTER ALL
Life exhibits extraordinary diversity over a broad range of size scales, and yet many of its most fundamental and complex phenomena scale with size in a surprisingly simple fashion. Geoffrey West of Los Alamos National Laboratory will lead off a session on complex real-world networks with a description of his quantitative theory explaining the origin of universal scaling. These networks include the cardiovascular, respiratory, and plant vascular systems, and can be extended in theory to growth, aging and mortality, ecosystems, and the nature of evolution, according to West. He will be joined by Luis Nunes Amaral of Boston University, who has studied the statistical properties of a variety of real-world, so-called "small world," networks, including the neural network of C. Elegans, transportation and technological networks, and numerous social networks. Other speakers will discuss the vulnerability of such networks, as well as the discovery that their emergence is driven by self-organizing processes governed by simple yet generic laws that can be captured with the tools of statistical mechanics. (Session L5, March 20)

THAT DARN CARBON
Climate change advocates extol the virtues of developing alternative energy sources ultimately to replace fossil fuels. But Princeton University's Robert Socolow believes that the global energy system can continue to be dominated by fossil fuels throughout the 21st century with an unacceptable rise in the concentration of atmospheric CO2. The key lies in capturing and storing a substantial fraction of the CO2 byproduct of burning fossil fuels, such as in geological formations like deep saline aquifers. Other speakers include John Stringer of EPRI, who will discuss carbon management in the electric power industry, and Exxon Mobil's Brian Flannery, who will approach the subject from the perspective of the oil industry. John Turned of the National Renewable Energy Laboratory will close the session with a counterpoint discussion of renewable energy technologies. (Session G7, March 19)

PROTECTING ASTRONAUTS ON THE WAY TO MARS
Without the protective covering of the Earth's atmosphere or the shield of its magnetosphere, an interplanetary spacecraft and its inhabitants are threatened by high-energy cosmic rays. While there is not much that can be done to forbid the entry of the highest energy particles, hazard engineers can at least try to minimize the dangerous debris produced inside the craft by cosmic ray strikes (the damage wrought by a charged particle scales as the square of the charge). Ram Tripathi of the NASA Langley Research Center (paper G26-5, Mar 19) suggests that the best material (protection per unit mass) might be resin composite materials reinforced with metal-atom-containing carbon nanotubes. Astronauts going to Mars, Tripathi says, will probably be male (female anatomy is more vulnerable) and of mature years (55 or older) owing to the cancer risks.

SMART PAINT AND THOUGHT-CONTROLLED MACHINES
Revolutionary advances in microfabrication and bioengineering are beginning to undercut some long-standing scientific assumptions about constructing and programming computers and robots. MEMS components are becoming less expensive, such that it may soon be possible to combine electronic and mechanical elements to produce particles that could be mixed with bulk materials, such as paints, gels and concrete. "Imagine coating bridges or buildings with smart paint that can sense and report on traffic and wind loads and monitor structural integrity of the bridge," says MIT's Gerald Sussman, in a talk called "Amorphous Computing" at session M2 (March 20). Alan Rudolph of DARPA will address the topic of whether our thoughts may one day control machines through cortical prosthetics that could extract and utilize motor and sensory commands. According to Rudolph, these commands have already been shown to drive a peripheral device in the control of a robotic arm. "New efforts," he writes, "will be aimed at examining the ability for humans to control peripheral devices replacing lost peripheral function or augmenting human performance." Paul Horn of IBM's T.J. Watson Research Center, this year's recipient of the APS George Pake Prize, will kick off the session with a discussion of the role for basic research in the information technology industry.

GOLDHABERS GALORE
Four talks and one prize mark the attendance of three generations of Goldhabers at this year's March APS meeting. David Goldhaber-Gordon (Stanford University) will present a survey of the Kondo effect in condensed matter physics when he accepts the George E. Valley Prize for outstanding contribution to physics by an individual younger than 30 (Session T6, March 21). The mechanisms underlying DNA editing by transposase proteins are the subject of a talk by David's wife Ilana Goldhaber-Gordon (Massachusetts Institute of Technology) in session F29 (March 19). David's father Alfred S. Goldhaber (State University of New York at Stony Brook) will discuss fractional quantum Hall layers in session Q18 (March 20), and his distinguished grandfather Maurice Goldhaber (Brookhaven National Laboratory) will take a closer look at elementary fermions in session L12 (March 20).

SLIME PROPULSION
Many types of bacteria get around by gliding across surfaces. Hair-like structures called pili propel the microorganisms when they travel in groups during herd-like migrations known in the field as social or s-type motility. The mechanism that bacteria use when they venture out alone (adventurous, or A-type, motility), however, has long been a mystery. Charles Wolgemuth (University of California at Berkeley) and coworkers think they have identified the vehicle that facilitates a bacterial walkabout - slime. Wolgemuth will present a slime propulsion model and experimental evidence for the unsavory conveyance in session F30 (Mar 19).

SWIRLING PLANKTON
Swarming is an excellent way for prey populations to confuse predators---even simple zooplankton include it among their survival behaviors. On rare occasions, the instinct can cause some plankton species to form a swirling vortex pattern that resembles a circling flock of birds preparing to roost. Anke Ordemmann and colleagues at the University of Missouri at St. Louis induced the freshwater zooplankton Daphnia to form circling swarms by attracting them with a vertical shaft of light. The researchers will exhibit the insights they have acquired by following individual Daphnia as they take part in the artificially induced plankton vortices (Session M30, Mar 20).

VIVE LA DIFF�RENCE
Sex, it seems, has both advantages and disadvantages. Ayse Erzan of the Istanbul Technical University has modeled some of the issues facing single-celled organisms that reproduce either through sexual pairing or through asexual division, and found clues that indicate why sex gives many organisms an evolutionary upper hand. Ezran's talk is one of a dozen in a session dedicated to the dynamics of evolution. Later in the session, Graeme Ackland (University of Edinburgh) and Michael Clark (Institute of Terrestrial Ecology, Scotland) will paint a picture of a world covered in flowers as they discuss the thermodynamics of an evolving system as it applies to Lovelock's "daisyworld"---a hypothetical two-dimensional world consisting of an infinite plain of daisies. The mechanisms that help clawed frogs detect their prey, optimal wiring in the cortex, and the molecular evolution of a genetic switch are just a few of the other subjects competing for attention in session U30 (March 21).

PUTTING A NEW FACE ON PHYSICS
Roman Czujko, director of the American Institute of Physics's Statistical Research Center, will give the latest data on education trends for African-Americans and Hispanic Americans with bachelor's and PhD degrees. Czujko will identify the physics departments that produce the most such degrees and describe the characteristics that successful departments have in common. He will be joined by Fernando Ponce of Arizona State University who will address the integration of Hispanics in physics. Other speakers will discuss opportunities for physicists in finance, in healthcare, and in the telecommunications industry. (Session D4, March 18)

GETTING MORE SCIENCE INTO SCIENCE KITS
In K-6 education, science kits are becoming increasingly popular; they are sometimes used in place of textbooks, as schools sometimes cannot afford to get both. Yet according to Richard Register of Princeton, the kit's instructional materials sometimes read like how-to manuals, and little more. Register will discuss a program, called the K-6 Science Curriculum Support Project (SCSP), which aims to supplement these kits' instructional materials with more scientific information, and tools to assess that the students have grasped the concepts that the kits intend to teach.(Session G9, March 19)

COMMUNICATING WITH CONGRESS
Now more than ever, with an uncertain economy and amid domestic terrorist threats, the scientific community needs to make itself heard on such issues as federal funding, climate change, ballistic missile defense, and many other notable issues. But many physicists have no idea how to get started. Introducing scientists to the whys and wherefores of the American legislative process is the focus of a special panel discussion featuring Washington insiders who will present the best techniques for communicating with Congress and the Executive Branch. Topics to be discussed include the differences between the science and policy worlds, how decisions are made in the policy world, and the best way scientists can provide input for those decisions, as well as opportunities for the scientific community to participate in Congressional visits. Participants will include former APS Congressional Fellow Sherri Stephan, a representative from the office of Senator Evan Bayh (D-IN), Donald Gubser of the Naval Research Laboratory, and Arthur Bienenstock of Stanford's Synchrotron Radiation Laboratory. (Session F5, March 19)

COMPUTER MEMORY THAT DOESN'T FORGET
When you turn off an ordinary computer, its RAM (random access memory) is lost. Jimmy Zhu of Carnegie Mellon University will describe a new memory technology, called magnetoresistive random access memory (MRAM), which is non-volatile: its memory is retained even after the computer is shut down. Whereas traditional RAM uses electric charge to store 0s and 1s of data, MRAM exploits the magnetic properties of electrons in the device. MRAM stores data by taking advantage of the fact that electrons act like tiny bar magnets in the presence of an magnetic field: 0 can represent the bar magnet when it is aligned with a field and 1 when it is opposite the direction of the field. MRAMs have many attractive features, yet a major drawback has been their relatively large power consumption: in traditional MRAM designs, less than 1% of the power is used to write the 0s and 1s of data, while over 99% of the power is wasted in delivering the electric current for writing the data. Zhu will present a novel memory device design that consumes significantly less power and is much more stable than previous designs. Such a design may bode well for miniaturizing this technology to the nanometer dimensions necessary for many commercial applications. (S6.001, March 21)

EDUCATING PHYSICISTS FOR THE WORKPLACE
Oftentimes, many physics-educated people do not call themselves physicists unless they have a Ph.D in physics. But many who earn bachelor's and masters degrees in the discipline use their knowledge of physics in their jobs, especially those in the industrial workplace. Session D7 (March 18) deals with strategies for educating physicists for industrial careers, from the bachelor's to Ph.D. levels. Ruth Howes of Ball State University will discuss a task force which has been gathering information from physics departments with thriving undergraduate programs. As Howes reports, "Many of these departments have innovative and successful strategies for providing students with career-building skills and information about employment opportunities." Bo Hammer of the Franklin Institute in Philadelphia will describe a Sloan Foundation-AIP study that has explored an emerging new degree in physics: the Professional Master's Degree, which is designed to meet the workforce and technical needs of industry.

Jennifer Ouellette of APS and James Riordon of AIP also contributed to the preparation of this press release.

For more information, see the Virtual Pressroom at http://www.aps.org/meet/MAR02/baps/vpr/