A unique polarized x-ray facility at the Advanced Photon Source

We present here direct experimental evidence of the magnetic polarization of Zn atoms in ZnO nanoparticles capped with different materials by means of x-ray magnetic circular dichroism ͑XMCD͒. Our results demonstrate that the magnetism in this material is intrinsic and relays in the ZnO conduction band. The analysis of both x-ray absorption spectroscopy and XMCD signals points out the formation of a well-defined interface between ZnO and the capping molecule in which the exotic magnetism arises at the hybridized band formed among Zn and the bonding atom of the molecule. The magnetic properties of these systems should critically depend on the details of this interface which may offer a new insight into the different observations for seemingly identical materials.

show abstract

“…10 Measurements were made in both fluorescence and total electron yield. No XMCD signal was observed independently of the detection mode.…”

Section: Methodsmentioning

confidence: 99%

Evidence of intrinsic magnetism in capped ZnO nanoparticles

et al. 2010

View full text Add to dashboard Cite

show abstract

“…10 XMCD measurements were performed at beamline 4-ID-C of Advanced Photon Source using a 7-T superconducting magnet. 11 The fluorescence yields at the Fe L 3 , Co L 2 , and Sm M 5 edges were used to record the element-specific hysteresis curves at 100 K at various spots on the samples ͑Fig. 2͒.…”

Section: Resultsmentioning

confidence: 99%

Interphase exchange coupling in Fe∕Sm–Co bilayers with gradient Fe thickness

Hattrick‐Simpers

Takeuchi

et al. 2005

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

We have fabricated Fe/ Sm-Co bilayers with gradient Fe thicknesses in order to systematically study the dependence of exchange coupling on the thickness of the Fe layer. The Fe layer was deposited at two different temperatures ͑150 and 300°C͒ to study the effect of deposition temperature on the exchange coupling. Magneto-optical Kerr effect and x-ray magnetic circular dichroism ͑XMCD͒ have been employed as nondestructive rapid characterization tools to map the magnetic properties of the gradient samples. Systematic enhancement in exchange coupling between the soft layer and the hard layer is observed as the soft layer thickness is decreased. Separate exchange couplings of the Fe layer with Co and Sm in the hard layer are revealed through measuring the element-specific hysteresis curves using XMCD. The single-phase-like magnetization reversal critical thickness increases from 12 nm for Fe deposited at 150°C to 24 nm for Fe deposited at 300°C, indicating an important role of the state of the interface in the exchange coupling.

show abstract

“…The performance of the UHV-compatible chopper system was tested at beamlines 4-ID-C [17] and 26-ID [18] of the Advanced Photon Source at Argonne National Laboratory. X-ray beams with photon energies between 0.6 and 12 keV were sent through the chopper system into the SX-STM, where the tip and sample currents were recorded.…”

Section: Methodsmentioning

confidence: 99%