Nuclear resonance reflectivity from a [<sup>57</sup>Fe/Cr]<sub>30</sub>multilayer with the Synchrotron Mössbauer Source

Andreeva,; Baulin, R. A.; Chumakov, A. I.; Rüffer, R.; Smirnov, G. V.; Babanov, Yu. A.; Devyaterikov, D. I.; Milyaev, M. A.; Ponomarev, D. A.; Romashev, L. N.; Ustinov, V. V.

doi:10.1107/s1600577517017192

Cited by 19 publications

(8 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, when the number of iron-57 atoms in the sample increases, the contribution of nuclear resonant scattering to total reflection is non-negligible, and a distorted spectrum appears due to interference with electronic scattering [20,39]. Recently, Andreeva et al investigated the Mössbauer reflectivity spectra of the [ 57 Fe(0.8nm)/Cr(1.05nm)] 30 multilayer film measured with π-polarized synchrotron Mössbauer γ-rays near the critical angle, and clarified the effects of polarization mixing of γ-rays emitted from the iron-57 layers and interference between electronic and nuclear resonant scatterings on the spectral profile [40]. In this system, they have also successfully demonstrated polarization analysis in Mössbauer reflectometry [41].…”

Section: Discussionmentioning

confidence: 99%

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Mitsui

Sakai

et al. 2021

Hyperfine Interact

View full text Add to dashboard Cite

Surface magnetism of Fe (001) was investigated by the in situ iron-57 probe layer method with a synchrotron Mössbauer source. The observed layer-by-layer internal hyperfine field shows a marked reduction at the surface and an oscillatory behavior with increasing depth in the individual layers below the surface. The calculated layer-by-layer hyperfine interactions (hyperfine field, isomer shift, and quadrupole shift) were consistent with the experimental results. The results give direct evidence for the magnetic Friedel oscillations, penetrating several layers from the Fe (001) surface.

show abstract

Section: Discussionmentioning

confidence: 99%

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Mitsui

Sakai

et al. 2021

Hyperfine Interact

View full text Add to dashboard Cite

show abstract

“…During the buffer layer deposition, the Al 2 O 3 substrate temperature was gradually decreased from 300 • C down to 180 • C. The typical deposition rate of Cr and 57 Fe layers was about of 0.15 nm/min. The details on the preparations and characterization of the samples can be found elsewhere [38]. The samples were mounted in the cassette holder of the He-exchange gas superconducting cryo-magnetic system.…”

Section: Resultsmentioning

confidence: 99%

“…For instance, for the structure with antiferromagnetic interlayer coupling between 57 Fe layers the angular and polarization dependencies for the spectrum lines are described by other polarization matrices than (3), (4) (see Ref. [38]).…”

Section: Theorymentioning

confidence: 99%

“…The key point of the SMS is the pure nuclear (111) or (333) reflection (forbidden for electronic diffraction) of the iron borate 57 FeBO 3 crystal, which provides a single-line purely π-polarized 14.4 keV radiation within the energy bandwidth of 8 neV. The crystal should be heated at a specific temperature close to the Neél point of 348.35 K. In comparison with the laboratory experiments, the application of the π-polarized beam results in new features of Mössbauer spectra measured with SMS in absorption or reflection geometry [38]. Use of a diamond phase plate in addition to the 57 FeBO 3 monochromator at the BL11XU beamline gives the new possibilities to perform measurements in forward and grazing-incidence geometries with various (linear, circular, elliptical) polarization states of radiation [39].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Polarization Analysis in Mössbauer Reflectometry with Synchrotron Mössbauer Source

et al. 2019

Self Cite

View full text Add to dashboard Cite

Polarization selection of the reflected radiation has been employed in Mössbauer reflectivity measurements with a synchrotron Mössbauer source (SMS). The polarization of resonantly scattered radiation differs from the polarization of an incident wave so the Mössbauer reflectivity contains a scattering component with 90° rotated polarization relative to the π-polarization of the SMS for some hyperfine transitions. We have shown that the selection of this rotated π→σ component from total reflectivity gives an unusual angular dependence of reflectivity characterized by a peak near the critical angle of the total external reflection. In the case of collinear antiferromagnetic interlayer ordering, the “magnetic” maxima on the reflectivity angular curve are formed practically only by radiation with this rotated polarization. The first experiment on Mössbauer reflectivity with a selection of the rotated polarization discovers the predicted peak near the critical angle. The measurement of the rotated π→σ polarization component in Mössbauer reflectivity spectra excludes the interference with non-resonant electronic scattering and simplifies the spectrum shape near the critical angle allowing for an improved data interpretation in the case of poorly resolved spectra. It is shown that the selected component of Mössbauer reflectivity with rotated polarization is characterized by enhanced surface sensitivity, determined by the “squared standing waves” depth dependence. Therefore, the new approach has interesting perspectives for investigations of surfaces, ultrathin layers and multilayers having complicated magnetic structures.

show abstract

“…The measured Mössbauer spectra of reflectivity at the two angles of incidence (inserts in Fig. 1(a), and their change under be entirely suppressed in the Mössbauer spectra at the "magnetic" ½ peak [36]. Thus, their appearance in the measured spectra evidences the non-collinear and asymmetrical alignment of magnetization.…”

mentioning

confidence: 80%

Double-spiral magnetic structure of the Fe/Cr multilayer revealed by nuclear resonance reflectivity

et al. 2018

View full text Add to dashboard Cite

We have studied the magnetization depth profiles in a [ 57 Fe(d Fe )/Cr(d Cr )] 30 multilayer with ultrathin Fe layers and nominal thickness of the chromium spacers d Cr  2.0 nm using nuclear resonance scattering of synchrotron radiation. The presence of a broad pure-magnetic half-order (½) Bragg reflection has been detected at zero external field. The joint fit of the reflectivity curves and Mössbauer spectra of reflectivity measured near the critical angle and at the "magnetic" peak reveals that the magnetic structure of the multilayer is formed by two spirals, one in the odd and another one in the even iron layers, with the opposite signs of rotation. The double-spiral structure starts from the surface with the almost antiferromagnetic alignment of the adjacent Fe layers. The rotation of the two spirals leads to nearly ferromagnetic alignment of the two magnetic subsystems at some depth, where the sudden turn of the magnetic vectors by ~180 o (spin-flop) appears, and both spirals start to rotate in opposite directions. The observation of this unusual double-spiral magnetic structure suggests that the unique properties of giant magneto-resistance devices can be further tailored using ultrathin magnetic layers.PACS numbers: 75.70. Cn, 75.25.+z, 76.80.+y Magnetization depth profiles in superlattices consisting of alternating layers of ferromagnetic (FM) and nonmagnetic or antiferromagnetic (AF) materials attract nonvanishing interest since 1986 when it was discovered [1] that AF interlayer exchange coupling (IEC) between adjacent Fe layers across a Cr spacer leads to the giant magnetoresistance effect [2,3]. This discovery brought in 2005 the Nobel prize to A. Fert and P. Grunberg. There are two widely studied features of the

show abstract

Nuclear resonance reflectivity from a [⁵⁷Fe/Cr]₃₀multilayer with the Synchrotron Mössbauer Source

Cited by 19 publications

References 65 publications

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Polarization Analysis in Mössbauer Reflectometry with Synchrotron Mössbauer Source

Double-spiral magnetic structure of the Fe/Cr multilayer revealed by nuclear resonance reflectivity

Contact Info

Product

Resources

About

Nuclear resonance reflectivity from a [57Fe/Cr]30multilayer with the Synchrotron Mössbauer Source

Cited by 19 publications

References 65 publications

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Direct observation of magnetic Friedel oscillation at Fe(001) surface

Polarization Analysis in Mössbauer Reflectometry with Synchrotron Mössbauer Source

Double-spiral magnetic structure of the Fe/Cr multilayer revealed by nuclear resonance reflectivity

Contact Info

Product

Resources

About

Nuclear resonance reflectivity from a [⁵⁷Fe/Cr]₃₀multilayer with the Synchrotron Mössbauer Source