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Beamline 4.0.2

Magnetic Spectroscopy

Operational

Now

Source characteristics

5.0-cm-period elliptical polarization undulator (EPU5)

Energy range

52-1900 eV

Monochromator

Variable-included-angle PGM

Calculated flux (1.9 GeV, 400 mA)

1 x 1013 photons/s/0.1%BW at 800 eV [Value reported is the merit function, flux = total flux x (degree of circular polarization)2.]

Resolving power (E/DE)

5,000-10,000 (at source-size limit; energy-dependent)
>25,000 (64 eV, 10-mm entrance/exit slits)

Special notes

Polarization is user selectable; linear polarization continously variable from horizontal to vertical; left and right elliptical (or circular) polarization.

Endstations

XMCD chamber
X-ray absorption chamber
Advanced photoelectron spectrometer/diffractometer
Gas-phase absorption cell
Spin spectrometer
MXCD cryo-chamber
L-edge chamber with superconducting spectrometer
XMCD chamber (6T, 2K)
Photoemission electron microscope

Local contacts

Name: Anthony T. Young
Phone: (510) 486-7746
Fax: (510) 486-7696
Email: atyoung@lbl.gov

Name: Elke Arenholz
Phone: (510) 486-4834
Fax: (510) 486-7588
Email: earenholz@lbl.gov

Spokesperson

Name: Stephen P. Cramer
Affiliation: Univ. of California, Davis/Berkeley Lab
Phone: (510) 486-4720
Fax: (510) 486-5664
Email: spcramer@lbl.gov

Beamline Phone Number

(510) 495-2041

 

Endstation

XMCD chamber

Characteristics

UHV chamber with an external electromagnet

Spatial resolution

None

Detectors

Sample current

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Up to 1 x 1 cm

Preparation

None

Sample environment

UHV, liquid N2 to room temperature

Special notes

Electromagnet: 0.25 Tesla

Scientific applications

Spectroscopy on ferromagnetic and antiferromagnetic materials

Experimental techniques

NEXAFS, XMCD, XMLD

Local contact

Name: Hendrik Ohldag
Phone: (510) 486-6645
Fax: (510) 486-2111
Email: hohldag@lbl.gov

Spokesperson

Name: Joachim Stöhr
Affiliation: Stanford Synchrotron Radiation Laboratory
Phone: (650) 926-2570
Fax: (650) 926-4100
Email: stohr@ssrl.slac.stanford.edu

 

Endstation

X-ray absorption chamber

Characteristics

Two positions for UHV or HV samples

Spatial resolution

None

Detectors

Total electron yield

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Any solid sample

Sample environment

10-9 Torr or <10-3 Torr behind a thin window

Special notes

Sample manipulator accommodates multiple samples; transmission experiments also possible

Scientific applications

XANES, EXAFS; MCD or MLD on samples with remanent magnetic field

Experimental techniques

Soft x-ray absorption

Local contacts

Name: Anthony T. Young
Phone: (510) 486-7746
Fax: (510) 486-7696
Email: atyoung@lbl.gov

Name: Elke Arenholz
Phone: (510) 486-4834
Fax: (510) 486-7588
Email: earenholz@lbl.gov

 

Endstation

Advanced photoelectron spectrometer/diffractometer

Characteristics

Rotatable analysis chamber, two-axis variable-temperature sample goniometer with 3-D translation operating between 150 and 2000 K; new goniometer extending to 10 K in mid-2002

Spatial resolution

10,000 ± 1.5° or ± 6°

Detectors

Scienta ES 200 electron spectrometer with micro-Mott spin detector (now) and Scienta XES 300 x-ray emission spectrometer (early 2002)

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

UHV-compatible solids up to 10 mm in diameter and 1-2 mm thick

Preparation

Knudsen-cell thin-film evaporation, ion sputtering, annealing, LEED, loadlock sample insertion, in-situ cleaving and magnetization

Sample environment

UHV, approximately 1 to 2 x 10-10 Torr

Special notes

Flexible and user-friendly control system; two detectors mounted on a rotating carousel enabling changes in ~30 min. without breaking UHV

Scientific applications

Electronic and magnetic properties at surfaces and interfaces, atomic and magnetic structures near surfaces and at buried interfaces, structural and magnetic phase transitions

Experimental techniques

High-resolution, angle-resolved photoelectron spectroscopy, diffraction and holography; x-ray absorption and x-ray emission spectroscopy

Local contact

Name:Norman Mannella
Phone: (510) 486-4581
Fax: (510) 486-5530
Email: nmannella@lbl.gov

Spokesperson

Name: Charles Fadley
Affiliation: Univ. of California, Davis/Berkeley Lab
Phone: (510) 486-5774
Fax: (510) 486-5530
Email: fadley@lbl.gov

 

Endstation

Gas-phase absorption cell

Characteristics

15-cm pathlength enclosed by thin windows, flowing or static sample

Spatial resolution

None

Detectors

Total ion current or x-ray transmission

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Any sample with adequate vapor pressure

Sample environment

<0.1 x 10-3 Torr to 5 x 10-3 Torr

Scientific applications

Spectroscopy on gas-phase systems

Experimental techniques

Soft x-ray absorption

Local contacts

Name: Anthony T. Young
Phone: (510) 486-7746
Fax: (510) 486-7696
Email: atyoung@lbl.gov

Name: Elke Arenholz
Phone: (510) 486-4834
Fax: (510) 486-7588
Email: earenholz@lbl.gov

 

Endstation

Spin spectrometer

Characteristics

Spin- and angle-resolved photoemission and absorption

Spatial resolution

None

Detectors

MCD hemispherical analyzer with spin- and angle-resolving capability

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Magnetic solids, thin films, and multilayers

Preparation

Sputter annealing and in-situ deposition

Sample environment

UHV, 150-1200 K

Special notes

360° angle-resolving analyzer with 2° angular resolution

Scientific applications

Polarization-dependent photoemission and x-ray absorption spectroscopies of advanced magnetic materials, half metals, nanostructures, and thin films

Experimental techniques

MXCD, SPXPS, SPUPS, MLDAD, AES, XPS, UPS, LEED, ARPES, ARSPUPS

Local contact

Name: Simon Morton
Phone: (510) 495-2926
Fax: (510) 486-7588
Email: samorton@lbl.gov

Spokesperson

Name: Dan Waddill
Affiliation: University of Missouri-Rolla
Phone: (573) 341-4111
Fax: (573) 341-4715
Email: waddill@umr.edu

 

Endstation

MXCD cryo-chamber

Characteristics

Closed-cycle cryostat-based system for MXCD and MLDAD at temperatuers down to 16 K in static or alternating magnetic fields

Spatial resolution

None

Detectors

Picoammeter drain current

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Magnetic solids

Preparation

In-situ cleaving of single-crystal samples

Sample environment

UHV, 16-400 K

Special notes

Sample magnetization by rare-earth permanent magnets or pulsed magnetic coils

Scientific applications

Magnetic spectroscopy of advanced single-crystal magnetic materials with low Curie temperatures or low remanence

Experimental techniques

MXCD, MLDAD, x-ray absorption

Local contact

Name: Simon Morton
Phone: (510) 495-2926
Fax: (510) 486-7588
Email: samorton@lbl.gov

Spokesperson

Name: Dan Waddill
Affiliation: University of Missouri-Rolla
Phone: (573) 341-4111
Fax: (573) 341-4715
Email: waddill@umr.edu

 

Endstation

L-edge chamber with superconducting spectrometer

Spatial resolution

None

Detectors

Nine-element array superconducting tunnel junction fluorescence detector; sample current

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Dried protein films, powders, thin films

Preparation

Proteins dried on Al2O3 disks, often in inert atmosphere; model compounds usually as powder on carbon tape

Sample environment

UHV, (10-8 to 10-9 Torr), cooling down to ~15 K possible

Special notes

Also analysis of wet and/or air-sensitive samples

Scientific applications

Active sites in metalloproteins, enzymatic mechanisms

Experimental techniques

Fluorescence-detected absorption spectroscopy

Local contact

Name: Stephan Friedrich
Phone: (510) 486-7319
Fax: (510) 486-5664
Email: sfriedrich@lbl.gov

Spokesperson

Name: Stephen P. Cramer
Affiliation: Univ. of California, Davis/Berkeley Lab
Phone: (510) 486-4720
Fax: (510) 486-5664
Email: spcramer@lbl.gov

 

Endstation

XMCD chamber (6T, 2K)

Characteristics

6-Tesla superconducting magnet, 2 K sample temperature

Spatial resolution

None

Detectors

30-element germanium fluorescence detector; sample current

Spot size at sample

1 mm (h) x 0.1 mm (v), larger if defocused

Samples

 

Format

Solids, powders, dried liquid films up to 5 x 5 mm

Sample environment

UHV

Scientific applications

Spectroscopy on proteins and model compounds

Experimental techniques

XMCD, L-edge spectroscopy

Local contact

Name: Tobias Funk
Phone: (510) 495-2889
Fax: (510) 486-5664
Email: funk@lbl.gov

Spokesperson

Name: Stephen P. Cramer
Affiliation: Univ. of California, Davis/Berkeley Lab
Phone: (510) 486-4720
Fax: (510) 486-5664
Email: spcramer@lbl.gov

 

Endstation

Photoemission electron microscope

Spatial Resolution

80 nm

Detectors

Photoemission electron microscope (PEEM)

Spot size at sample

90 x 60 µm

Samples

 

Format

Single crystals and thin films grown in situ (metals and oxides), sample transfer from air through load-lock; maximum sample size 10 x 10 x 2 mm.

Preparation

Ion bombardment, annealing, oxidation, magnetization

Sample environment

UHV

Special notes

Sample preparation chamber for in-situ growth; Io chamber with 20-mm slits for XAS, XMCD, XMLD

Scientific applications

Investigations of magnetic nanostructures

Experimental techniques

PEEM, XAS, XMCD, XMLD, MOKE, LEED, AES

Local contact

Name: Joerg Schneider
Phone: (510) 486-7249
Fax: (510) 486-7588
Email: jschneider@lbl.gov

Spokesperson

Name: Boris Sinkovic
Affiliation: University of Connecticut
Phone: (510) 486-6344
Fax: (510) 486-3346
Email: sinkovic@uconnvm.uconn.edu

 

Table of all beamlines
Diagram of all beamlines