Observation of a Macroscopically Quantum-Entangled Insulator
It has recently been proposed that insulators with large band gaps and strong spin-orbit coupling can host a new phase of quantum matter called a topological insulator that is characterized by entangled wavefunctions. The proposal has now been realized by an international collaboration led by researchers from Princeton University who studied the electronic structure of insulating alloys of bismuth and antimony by means of angle-resolved photoemission spectroscopy (ARPES) and spin-resolved ARPES. Their results constitute the first direct experimental evidence of a topological insulator in nature that is fully quantum entangled. In the future, a detailed study of topological order and quantum entanglement using their method can potentially pave the way for fault-tolerant (topological) quantum computing. Read more…
Publication about this research: D. Hsieh, Y. Xia, L. Wray, D. Qian, A. Pal, J.H. Dil, J. Osterwalder, F. Meier, G. Bihlmayer, C.L. Kane, Y.S. Hor, R.J. Cava, and M.Z. Hasan, “Observation of unconventional quantum spin textures in topological insulators,” Science 323, 919 (2009).
P-Glycoprotein Structure and Chemotherapy Resistance
A research team from the Scripps Research Institute and the Texas Tech University Health Sciences Center has obtained the first glimpse of a protein that keeps certain substances, including many drugs, out of cells. The protein, called P-glycoprotein, or P-gp for short, is one of the main reasons cancer cells are resistant to chemotherapy drugs. Understanding its structure may help scientists design more effective drugs. The structure is a nice tool for understanding how drugs are transported out of cells by P-gp and for designing drugs to evade P-gp, preventing drug resistance. Read more…
Publication about this research: S.G. Aller, J. Yu, A. Ward, Y. Weng, S. Chittaboina, R. Zhuo, P.M. Harrell, Y.T. Trinh, Q. Zhang, I.L. Urbatsch, and G. Chang, “Structure of P-glycoprotein reveals a molecular basis for poly-specific drug binding,” Science 323, 1718 (2009).
Molecular-Frame Angular Distributions of Resonant Auger Electrons
Molecular-frame electron angular distribution (MFAD) measurements provide access to an unprecedented level of detailed information about phenomena involving quantum coherence, such as phases of photoelectron waves, symmetry breaking in molecular dissociation, core-hole localization in molecules, and molecular double-slit interference, all of which are hidden in conventional gas-phase electron spectroscopy, owing to the random orientation of the molecules. While most MFAD studies to date have focused on photoelectrons, an international team of scientists from Western Michigan University, the ALS, and Tohoku University in Japan has successfully used a novel approach to determine for the first time the molecular-frame angular distributions of resonantly excited Auger electrons in carbon monoxide. Read more…
Publication about this research: D. Rolles,G. Prumper, H. Fukuzawa, X.-J. Liu, Z.D. Pesic, R.F. Fink, A.N. Grum-Grzhimailo, I. Dumitriu, N. Berrah, and K. Ueda, “Molecular-frame angular distributions of resonant CO:C(1s) Auger electrons,” Phys. Rev. Lett. 101, 263002 (2008).
ALS to Participate in Energy Frontier Research Centers
On April 27, the Department of Energy’s Office of Science announced 46 Energy Frontier Research Centers (EFRCs) that will share 2 and 5 million that will support research with the aim of accelerating scientific breakthroughs in the fields of solar energy, electricity storage, materials sciences, advanced nuclear systems and carbon capture and sequestration.
The ALS will be used by three of the EFRCs. The Center for Nanoscale Control of Geologic CO2, run out of Berkeley Lab, with collaborators from Lawrence Livermore National Laboratory, Massachusetts Institute of Technology, and the University of California, Davis, will look at scientific foundations for the geological storage of carbon dioxide and how they are related to reducing greenhouse gases released to the atmosphere from stationary power sources. Developing computational tools to accurately model catalytic reactions and thereby provide the basis for the design of new catalysts will be the focus of a second EFRC to be established at Louisiana State University. Finally, the EFRC for Combustion Science will focus on the science underlying the development of non-petroleum-based fuels, including carbon-neutral biofuels, and their optimal use in transportation. This collaboration comprises 15 members from seven universities, and Sandia and Argonne National Laboratories. This group will address the goal to develop a “validated, predictive, multi-scale, combustion modeling capability to optimize the design and operation of evolving fuels in advanced engines for transportation applications.” As part of this Center, Nils Hansen of Sandia National Laboratories will perform experiments at the “Flame-Sampling Endstation” of the Chemical Dynamics Beamline (Beamline 9.0.2). The Center will take full advantage of the unique capabilities of the ALS to provide an unprecedented detailed data set to test combustion chemistry models and to determine key reaction pathways in real combustion environments. Synopses of all the EFRCs are available in PDF format.
UEC Corner: Mark Your Calendars for the 2009 Users’ Meeting
Please save the date for the 2009 ALS/Molecular Foundry Users’ Meeting, Thursday, October 15 through Saturday, October 17, 2009. This year’s meeting will be hosted jointly with The Molecular Foundry (TMF) and will have a primary focus on basic research to further the United States’ and the world’s energy agenda. The conference program includes plenary talks, talks given by selected attendees and award recipients, a joint poster session with TMF, and twelve workshops. See the Users’ Meeting Web page for titles and organizers, updated as the information becomes available.
Please keep in mind the following deadlines:
Poster Abstract Submission: Monday, 8/31/2009
We look forward to seeing you at the 2009 ALS/TMF Users’ Meeting.
2009 Users’ Meeting co-chairs
Reminder: ALS Fellowship Programs Available
The ALS offers two types of research fellowships: the Doctoral Fellowship in Residence (applications due July 31, 2009) and the Postdoctoral Fellowship (applications reviewed quarterly).
ALS Doctoral Fellowship in Residence enable students who have passed their Ph.D. qualifying or comprehensive verbal and written exams to acquire hands-on scientific training and develop professional maturity for independent research. Applicants must be full-time, currently enrolled students in a Ph.D. program in the physical or biological sciences pursuing thesis research based on the use of synchrotron radiation. The fellowships are offered as one-year appointments with the possibility of renewal. Successful applicants will be compensated with an $18,000 annual stipend. Additionally, fellows will be matched with an on-site mentor and have access to ALS resources, including beam time. Fellows are expected to present their results at a meeting or as a seminar at the end of the fellowship year. Applications for the 2009-10 academic year are due by July 31, 2009. For more information, go to the ALS Doctoral Fellowships Web page.
The purpose of the ALS Postdoctoral Fellowship Program is to identify outstanding individuals in new and emerging scientific and engineering research fields and provide advanced training in synchrotron radiation science. It also provides the opportunity to identify outstanding scientists in historically underrepresented groups. Fellows become integral members of ALS research teams. Applicants must have received a doctoral research degree from an accredited academic institution in an appropriate scientific or engineering discipline within three years of the appointment start date. Applications are reviewed on a quarterly basis. Awards are initially for one year with the possibility of renewal for a second or third year, contingent on satisfactory annual performance reviews and funding availability. A monthly salary will be paid at a rate competitive with current ALS/LBNL postdoctoral fellows. Postdoctoral fellows are also eligible for midlevel career benefits. For more information on the fellowship and application requirements, go to the ALS Postdoctoral Fellowships Web page.
BESAC Photon Workshop Report Now Posted Online
The U.S. Department of Energy’s Basic Energy Sciences Advisory Committee (BESAC) sponsored a series of workshops about “Basic Research Needs” to help identify research directions for a decades-to-century energy strategy. A newly published report from this series, titled “Next Generation Photon Sources for Grand Challenges in Science and Energy ,” summarizes the results of the Photon Workshop held in October 2008, co-chaired by Wolfgang Eberhardt and Franz Himpsel. The “Photon Report” identifies connections between major new research opportunities and the capabilities of the next generation of light sources. Particular emphasis was on energy-related research. Please feel free to download the report and distribute it to colleagues in the scientific community.
For the user runs from April 15 to May 11, the beam reliability [(time scheduled – time lost)/time scheduled)] was 96.1%. For this period, the mean time between failures (MTBF) was 23.8 hours, and the mean time to recovery (MTTR) was 44 minutes. There were no significant interruptions.
More detailed information on reliability is available on the ALS reliability bulletin board, which is located in the hallway between the ALS and the control room in Building 80. Questions about beam reliability should be sent to David Richardson.
Long-term and weekly operations schedules are available here. Requests for special operations use of the “scrubbing” shift should be sent to Rick Bloemhard (ALS-CR@lbl.gov, x4738) by 1:00 p.m. Friday. View the ring status in real time here.