1. ANTIFERROMAGNETIC SPIN REORIENTATION
by Art Robinson
(Contact: HOhldag@lbl.gov)

One of the vexing mysteries facing researchers in magnetic materials is the origin of the exchange-bias effect in which an antiferromagnetic layer pins the magnetization of an adjacent ferromagnetic layer so that it doesn't reverse in an external magnetic field. Building on earlier work with the photoemission electron microscope (PEEM) on Beamline 7.3.1.1 at the Advanced Light Source, a German-American collaboration has taken an important step toward unveiling the secret of exchange bias by observing that spins near a nickel oxide antiferromagnet's surface reorient after deposition of a cobalt ferromagnetic layer. This discovery rules out models of exchange bias based on the common assumption that the spin configuration at the surface of the antiferromagnet is the same as that in its interior (bulk).

Read the full story at http://www-als.lbl.gov/als/science/sci_archive/peem_spin.html.

Publication about this research: H. Ohldag, A. Scholl, F. Nolting, S. Anders, F.U. Hillebrecht, and J. Stohr, "Spin reorientation at the antiferromagnetic NiO(001) surface in response to an adjacent ferromagnet," Phys. Rev. Lett. 86, 2878 (2001).

2. LOCAL SEMINAR SCHEDULE NOW AVAILABLE ONLINE
(Contact: AMGreiner@lbl.gov)

Curious about quantum-dot lattices or the nuclear lighthouse effect? Wondering about the latest developments in femtosecond-pulse research or the latest hardware developments at ELETTRA? A wide variety of seminars and meetings occur in and around the ALS every week that are of potential interest to many people beyond those working on site day in and day out. Now, everyone, including nonlocal users who will be in town for an experiment run and "semilocal" ones who reside in the Bay Area, can learn in advance about ALS-related seminars and meetings by checking the Web at http://www-als.lbl.gov/als/workshops/recurring.html (the page can also be reached via the "Recurring local seminars" link on the Meetings and Workshops page). The online schedule includes speakers, topics, times, and locations for upcoming seminars and meetings and is updated as needed--so bookmark the page and check back often!

3. JOB OPPORTUNITIES AT THE ALS

Listed below are a few ALS-related positions that are currently available. For more detailed information on a specific job, go to the Berkeley Lab Current Job Opportunities Web page (http://cjo.lbl.gov/), type the Job Requisition Number (shown below in parentheses) into the keyword search box, and click on the "GO" button (do not use the "return" key). For a complete listing of ALS-related openings, search on the keywords "Advanced Light Source."

Computer Scientist (012553). Develop computational methodology and instrumentation for collecting and analyzing crystallographic data using synchrotron radiation. Participate in projects involving the structure determination of biological molecules and biomolecular complexes.

Scientific Engineering Associate (012711). Play a lead role in the development of soft x-ray synchrotron radiation facilities in advanced microscopy and spectroscopy techniques specific to molecular environmental science (MES). Two-year appointment with the possibility of renewal.

Physicist Scientist/Engineer (013302). As an accelerator physicist, advise ALS management on activities aimed at detailed understanding of the ALS accelerators; collaborate with physicists, engineers, and technical support staff to perform planned experiments; publish results in peer-reviewed journals and present the results at conferences. Two-year appointment with the possibility of renewal.

Computer Systems Engineer I (Intern) (013487). Develop and support software that controls accelerator and beamline systems and collects, manages, and processes scientific data. One-year appointment with the possibility of renewal and/or conversion to career.

Executive Assistant (013580). Assigned to the ALS/Materials Sciences Division Director, provides executive-level assistance by representing the Director to various internal and external stakeholders, screening incoming communication, managing the Director's calendar, preparing correspondence and management presentations, and organizing meetings, conferences, and annual reviews.

Student Assistant (013359). As a summer student, assist with programmatic activities, such as taking data, working on accelerator hardware, and using the computer for simulations and calculations; assist in the design and fabrication of technical components; and provide logistical support. There is more than one opening for this position.

4. WHO'S IN TOWN: A SAMPLING OF ALS USERS

Following are some of the experimenters who will be collecting data during the next two weeks at the ALS.

Beamline 1.4.3
Hoi-Ying Holman (Berkeley Lab)
Tom Breunig and Dan Fried (Univ. of California, San Francisco)
Ted Raab (Carnegie Institution of Washington)
Felicia Betancourt and Bob Glaeser (Univ. of California, Berkeley, and Berkeley Lab)
Kelly Knutsen and Rich Saykally (Univ. of California, Berkeley)

Beamline 5.3.1
Christian Bressler (Univ. of Lausanne, Switzerland)
Melanie Saes (Univ. of Lausanne, Switzerland)
Raphael Abela (Paul Scherrer Institut, Switzerland)

Beamline 7.3.1.1
Adam Hitchcock (McMaster Univ., Canada)
Simone Anders (IBM Almaden Research Center)

Beamline 7.3.3
Bryan Valek (Stanford Univ.)
Ralph Spolenak (Lehigh Univ.)

Beamline 8.0.1
Fred Schlachter (Berkeley Lab)
Wayne Stolte (Berkeley Lab
Dave Ederer (Tulane Univ.)
Tom Callcott (Univ. of Tennessee, Knoxville)
Alex Moewes (Univ. of Saskatchewan, Canada)

Beamline 9.0.2
Andy Kung (Academia Sinica, Taiwan)
Matthias Kling (Univ. of Gottingen, Germany)

Beamline 9.3.2
Sefik Suzer (Brookhaven National Laboratory and Bilkent Univ., Turkey)
Pasl A. Jalil (King Fahd Univ. of Petroleum and Minerals, Saudi Arabia)
M. Faiz (King Fahd Univ. of Petroleum and Minerals, Saudi Arabia)

5. OPERATIONS UPDATE
(Contact: Lampo@lbl.gov)

For the user runs of May 22 - 27 and May 31 - June 3, the beam reliability (time delivered/time scheduled) was 97%. Of the scheduled beam, 89% was delivered to completion without interruption. There were no significant outages.

Long-term and weekly operations schedules are available on the Web (http://www-als.lbl.gov/als/accelinfo.html). Requests for special operations use of the "scrubbing" shift should be sent to Bruce Samuelson (BCSamuelson@lbl.gov, x4738) by 1:00 p.m. Friday. The Accelerator Status Hotline at (510) 486-6766 (ext. 6766 from Lab phones) features a recorded message giving up-to-date information on the operational status of the accelerator.

LBNL/PUB-848
Editors: lstamura@lbl.gov, alrobinson@lbl.gov, amgreiner@lbl.gov

This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.