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The electronic structure and the domain wall width of industrial (Nd,Dy)$_{2}$Fe$_{14}$B hard magnets were investigated using low-temperature, spin-polarized scanning tunneling microscopy (STM) in ultra-high vacuum. In a first step, atomically clean and flat surfaces were prepared. The flat terraces were separated by monatomic steps. Surface termination was identified as the Fe c layer from atomically resolved STM imaging. The electronic density of states and its spin polarization agree well with ab initio predictions of the Fe c layer. High-resolution spin-polarized STM images allowed to finally resolve the domain wall width w of only 3.2 ± 0.4 nm.

In this work, we study the spin polarization in the MoS(Se)2–WS(Se)2 transition metal dichalcogenide heterostructures by using the non-equilibrium Green’s function method and a three-band tight-binding model near the edges of the first Brillouin zone. Although it has been shown that the structures have no significant spin polarization in a specific range of energy of electrons, by applying a transverse electric field in the sheet of the metal atoms, shedding light on the sample, and under a small bias voltage, a significant spin polarization in the structure could be created. Besides, by applying a suitable bias voltage between leads and applying the electric field, a noticeable spin polarization can be found even without shedding the light on the heterostructures.

We explore the spin-polarization of quark matter in the NJL model including the scalar and tensor interactions. There are two kinds of spin-polarized phases: one appears in the chiral-broken phase where the quark mass is non-zero, and the other in the chiral-restored phase where the quark mass is zero.

It is recently noted that in certain centrosymmetric compounds, spin-orbit interaction couples each local sector that lacks inversion symmetry and thus leads to visible spin polarization effects in the real space, dubbed as 'hidden spin polarization (HSP)'. However, observable spin polarization of a given local sector suffers interference by its inversion partner, impeding material realization and potential applications of HSP. Starting from a single-orbital tight-binding model, we propose a nontrivial way to protect strong sector-projected spin texture through minimizing the interaction between inversion partners by nonsymmorphic symmetry. The HSP effect is generally compensated by inversion partners near the {\Gamma} point but immune from interaction around the boundary of the Brillouin zone. We further summarize 17 layer groups that support such symmetry-assisted HSP and identify by first-principle calculations hundreds of quasi-2D materials from the existing databases, among which a group of rare-earth compounds LnOI (Ln = Pr, Nd, Ho, Tm and Lu) serves as great candidates showing strong Rashba- and Dresselhaus-type HSP. Our finding also provides an ideal platform to control HSP for emergent physical effects, such as opening a hybridization gap by tensile strain to realize the time-reversal-invariant topological superconductivity., Comment: 16 pages, 1 table, 3 figures

Synopsis A complex optical potential (OP) is employed within the framework of the Dirac partial wave method to study the critical minima (CM) in the differential cross sections and the spin polarization for the elastic scattering of electrons by the Sr atom in the energy range Ei = 1-1000 eV. The complex optical potential is composed of the static, exchange, polarization and absorption potentials. The number of CM points has been found to be 7 in the DCSs of e-Sr scattering, while the number of maximum spin polarization points observed is 13.

Within the framework of the complex optical potential, the critical minima (CM) in the differential cross sections and the spin polarization in the elastic scattering of electrons by the Sr atom are studied in the energy range E i = 1–1000 eV using the Dirac and Schrödinger partial wave methods. The two methods are, respectively, termed as the optical potential method of Dirac (OPMD) and optical potential method of Schrödinger (OPMS). The differential cross sections (DCSs), total cross sections (TCSs), momentum transfer cross sections (MTCSs), integral elastic cross sections (IECSs), viscosity cross sections (VCSs) and inelastic cross sections (INCSs) for e–Sr scattering are also calculated for the same energy range. In OPMD, the complex optical potential is composed of the static, exchange, polarization and absorption potentials. The OPMS potential, on the other hand, comprises the static, local exchange, polarization, spin-orbit, and absorption components. The number of CM points has been found to be respectively 7 and 5 with OPMD and OPMS methods in the DCSs of e–Sr scattering. The number of maximum spin polarization points observed is 13 and 10 for the OPMD and OPMS respectively. The energy dependence of TCS, MTCS, IECS, VCS, and INCS, studied in this work, show a non-monotonous pattern for energies beyond about 50 eV. So far as we are concerned, this is the first work for the study of CM in the DCSs of the e–Sr scattering as there are neither experimental nor theoretical studies published in the literature for the same.

The BESIII collaboration here reports the first observation of polarized $\Lambda$ and $\bar{\Lambda}$ hyperons produced in two different processes: i) the resonant $e^+e^- \to J/\psi\to\Lambda\bar{\Lambda}$, using a data sample of 1.31 $\times$ 10$^9$ $J/\psi$ events and ii) the non-resonant $e^+e^-\to \gamma^* \to \Lambda\bar{\Lambda}$, using a 66.9 pb$^{-1}$ data sample collected at $\sqrt{s} =$ 2.396 GeV. In $e^+e^-\to J/\psi\to\Lambda\bar{\Lambda}$, the phase between the electric and the magnetic amplitude is measured for the first time to be $42.3^{\mathrm{o}} \pm 0.6^{\mathrm{o}} \pm 0.5^{\mathrm{o}}$. The multi-dimensional analysis enables a model-independent measurement of the decay parameters for $\Lambda\to p\pi^-$ ($\alpha_-$), $\bar{\Lambda}\to\bar{p}\pi^+$ ($\alpha_+$) and $\bar{\Lambda}\to\bar{n}\pi^0$ ($\bar{\alpha}_0$). The obtained value $\alpha_-=0.750\pm0.009\pm0.004$ differs with ~5$\sigma$ from the PDG value. This value, together with the measurement $\alpha_+=-0.758\pm0.010\pm0.007$ allow for the most precise test of CP violation in $\Lambda$ decays so far: $A_{CP} = (\alpha_- + \alpha_+)/(\alpha_- - \alpha_+)$ of $-0.006\pm0.012\pm0.007$. The decay asymmetry $\bar{\alpha}_0 = -0.692\pm0.016\pm0.006$ is measured for the first time. The $e^+e^- \to \Lambda\bar{\Lambda}$ reaction at $\sqrt{s} =$ 2.396 GeV enables a first complete measurement of the time-like electric and magnetic form factor of any baryon, of the modulus of the ratio $R=|G_E/G_M|$ and of the relative phase $\Delta\Phi=\Phi_E-\Phi_M$. With the decay asymmetry parameters from the $J/\psi$ data, the obtained values are $R=0.96\pm0.14\pm0.02$ and $\Delta\Phi = 37^{\mathrm{o}} \pm 12^{\mathrm{o}} \pm 6^{\mathrm{o}}$. In addition, the cross section has been measured with unprecedented precision to be $\sigma = 119.0\pm 5.3\pm5.1$ pb, which corresponds to an effective form factor of $|G|=0.123 \pm 0.003 \pm 0.003$., Comment: 1 Talk at BEACH 2018

In this study, we investigate the effect of rotation on the masses of scalar and vector mesons in the framework of the 2-flavor Nambu-Jona-Lasinio model. The existence of rotation produces a tedious quark propagator and a corresponding polarization function. By applying the random phase approximation, the meson mass is numerically calculated. It is found that the behavior of scalar and pseudoscalar meson masses under angular velocity ω is similar to that at a finite chemical potential; both rely on the behavior of the constituent quark mass and reflect the property related to chiral symmetry. However, vector meson ρ masses have a more profound relation to rotation. After analytical and numerical calculations, it turns out that at low temperature and small chemical potential, the mass for spin component of a vector meson under rotation exhibits a very simple mass splitting relation , similar to the Zeeman splitting of a charged meson under magnetic fields. Furthermore, the mass of the spin component of vector meson ρ decreases linearly with ω and reaches zero at , which indicates that the system will develop vector meson condensation and the system will be spontaneously spin-polarized under rotation.

The spin-polarization S and the spin-polarization parameters U and T of the elastically scattered electrons from Hg atoms have been computed for scattering angles 0°–180° in the energy range 1 eV . An optical model approach is employed using a complex optical potential within the framework of the Dirac relativistic partial wave analysis. We compare our results with recent experiments and available theoretical calculations and find a reasonable agreement with experiments over a wide range of energies.

The spin-resolved Auger decay of the Ar 2p-11/2 3d state was measured at moderate energy resolution and compared with the decay of the 2p-11/2 4s. The former shows a lower transferred spin polarization and a similar, if not higher, dynamical spin polarization, supporting the statement that a fully resolved spectrum is not a necessary condition for observing dynamical spin polarization. An interpretation of the spin polarization as configuration interaction induced effect in the final ionic state leads to partial agreement with our relativistic distorted wave calculation utilizing a 36 configuration state function basis set. Comparison of the experimental and numerical results leads to ambiguities for at least one Auger line. A hypothetical, qualitative interpretation is discussed.

A number of recent experiments report spin polarization in quantum wires in the absence of magnetic fields. These observations are in apparent contradiction with the Lieb-Mattis theorem, which forbids spontaneous spin polarization in one dimension. We show that sufficiently strong interactions between electrons induce deviations from the strictly one-dimensional geometry and indeed give rise to a ferromagnetic ground state in a certain range of electron densities., 4 pages, 4 figures

A macroscopic model of the dissipative magneto-elastic dynamics of viscous spin polarized nuclear matter is discussed in the context of seismic activity of a paramagnetic neutron star. The source of the magnetic field of such a star is attributed to Pauli paramagnetism of baryon matter promoted by a seed magnetic field frozen into the star in the process of gravitational collapse of a massive progenitor. Particular attention is given to the effect of shear viscosity of incompressible stellar material on the timing of non-radial torsional magneto-elastic pulsations of the star triggered by starquakes. By accentuating the fact that this kind of vibration is unique to the seismology of a paramagnetic neutron star we show that the high-frequency modes decay faster than the low-frequency modes. The obtained analytic expressions for the period and relaxation time of this mode, in which the magnetic susceptibility and viscosity enter as input parameters, are then quantified by numerical estimates for these parameters taken from early and current works on transport coefficients of dense matter. It is found that the effect of viscosity is crucial for the lifetime of magneto-torsion vibrations but it does not appreciably affect the periods of this seismic mode which fall in the realm of periods of pulsed emission of soft gamma-ray repeaters and anomalous x-ray pulsars—young super-magnetized neutron stars, radiating, according to the magnetar model, at the expense of the magnetic energy release. Finally, we present arguments that the long periodic pulsed emission of these stars in a quiescent regime of radiation can be interpreted as a manifestation of weakly damped seismic magneto-torsion vibrations exhibiting the field induced spin polarization of baryon matter.

Experimental studies of spin transport in a two-dimensional electron gas hosted by a triple GaAs/AlGaAs quantum well are reported. Using time-resolved Kerr rotation, we observed the precession of the spin polarization about a current-controlled spin-orbit magnetic field. Spatially-resolved imaging showed a large variation of the electron g-factor and the drift transport of coherent electron spins over distances exceeding half-millimetre in a direction transverse to the electric field., Proceedings of the 33rd International Conference on the Physics of Semiconductors (ICPS) 2016

The stabilized jellium model (SJM) provides us with a method for calculating the volume changes of different simple metals as functions of the spin polarization, ζ, of the delocalized valence electrons. Our calculations show that for bulk metals, the equilibrium Wigner-Seitz (WS) radius, sB(ζ), is always an increasing function of the polarization, i.e., the volume of a bulk metal always increases as ζ increases, and the rate of increase is higher for higher-electron-density metals. Using the SJM along with the local spin-density approximation, we have also calculated the equilibrium WS radius, s(N,ζ), of spherical jellium clusters, at which the pressure on the cluster with given number of total electrons N with spin configuration ζ vanishes. Our calculations for Cs, Na, and Al clusters show that s(N,ζ) as a function of ζ behaves differently depending on whether N corresponds to a closed-shell or an open-shell cluster. For a closed-shell cluster, it is an increasing function of ζ over the whole range 0≤ζ≤1, whereas for open-shell clusters it has a decreasing behaviour over the range 0≤ζ≤ζ0, where ζ0 is a polarization such that the cluster has a configuration consistent with Hund's first rule. The results show that for all neutral clusters with the ground-state spin configuration, ζ0, the inequality s(N,ζ0)≤sB(0) always holds (self-compression) but, at some polarization ζ1>ζ0, the inequality changes direction (self-expansion). However, the inequality s(N,ζ)≤sB(ζ) always holds and equality is achieved in the limit N→∞.

We consider a class of relativistic quantum systems of ring geometry with mass confinement, subject to a magnetic flux. Such a system supports a family of boundary modes with edge-dependent currents and spin polarization as the spinor-wave analog of the whispering-gallery modes. While these states are remarkably robust against random scattering, boundary deformations and/or bulk disorders can couple the two oppositely circulating base states. Superposition of the two states can be realized by sweeping an external magnetic flux. We also address the issue of decoherence and articulate a possible experimental scheme based on 3D topological insulators. Copyright (C) EPLA, 2016

It is shown that a complete photoelectron-spin polarization occurs independent of emission angle for two special sets of values of the dynamical photoionization parameters. In spin- and angle-resolved photoelectron spectroscopy of thallium the dynamical parameters were measured near the autoionization resonances at 149 nm and 82 nm. A pronounced angular variation of the polarization component A[Theta] was observed at 83 nm. For both resonances the parameters were found to approach different limiting values such that the length of the spin-polarization vector assumes values close to unity at all emission angles. The implications of these results for the corresponding dipole transition matrix elements are discussed.

Quantum transport that takes into account spin polarization has a high potential for research on optimal heterostructures for fabrication of nano-spintronic devices and quantum computing. This work theoretically analyzed different materials on the basis of type-II strained heterostructures like InAs/GaSb, InSb/GaSb, InSb/GaAs, and GaSb/GaAs by means of the spin polarization that considers the interacting spin coupling type: k3- Dresselhaus and Rashba in the electric barriers and the influence of in-plane magnetic field on spin polarization. The results obtained for the polarization of spin are in function of the energy applied to the electron, well width, height of barrier, and magnetic field intensity. This suggests that these features could be engineered in the fabricating of tunable spin- dependent electronic devices, such as spin switches based on double-barrier non-magnetic semiconductors.

The spin-resolved electronic band structure of Au-induced metallic atomic wires on a vicinal silicon surface, Si(553), was investigated using spin- and angle-resolved photoelectron spectroscopy. We directly measured the spin polarization of three partially filled one-dimensional metallic bands, a one-third-filled band, and the doublet of nearly half-filled bands. For the half-filled doublet, the strong apparent spin polarization was observed near the Fermi energy with a minor out-of-plane spin component. This observation is consistent with the Rashba-type spin-orbit splitting and with a recent experiment on a similar doublet of Si(557)-Au. In contrast, the one-third-filled band does not show a substantial spin polarization within the experimental accuracy, indicating a much smaller spin splitting, if any. These results are discussed for the origin of the partially filled bands and for the intriguing broken-symmetry ground state observed at low temperature.

We present first experimental data on the theoretically predicted effect [1] that photoelectrons created by ionization of noble gas atoms in an intense laser field are spin polarized.

We demonstrate boundary spin polarization at the surface of a Cr2O3 single crystal using spin-polarized low-energy electron microscopy (SPLEEM), complementing prior spin polarized photoemission, spin polarized inverse photoemission, and x-ray magnetic circular dichroism photoemission electron microscopy measurements. This work shows that placing a Cr2O3 single crystal into a single domain state will result in net Cr2O3 spin polarization at the boundary, even in the presence of a gold overlayer. There are indications that the SPLEEM contrast for the two polarization states may be different, consistent with scanning tunneling microscopy spectroscopy results obtained from ultrathin films of Cr2O3.

Spin polarization measurement is important for the study of a variety of spin states in quantum Hall system. Kerr rotation is proportional to spin polarization, so we developed a high sensitive measurement of Kerr rotation by using homodyne detection and a variety of modulation techniques. Furthermore, we developed Kerr rotation spectra measurement system base on the multi-channel homodyne detection, which enables the assignment of the optical transitions and semi-quantitative estimation of spin polarization by integrating the spectra over the specific optical transition. The spin polarization presents a rapid spin depolarization on both sides of ? = 1 due to Skyrmionic excitation. However the top of spin polarization presents a narrow flat region. Furthermore the spin polarization around ? = 3 also shows a rapid spin depolarization which suggest the existence of Skyrmion at higher odd filling factor.

We report on the transport behavior and spin polarization P of carriers for superconductor/ferromagnetic semiconductor (S-F) junctions. We fabricated Nb/ferromagnetic semiconductor p-In0.96Mn0.04As junctions with Hall voltage probes. Below ~15 K, p-In0.96Mn0.04As becomes ferromagnetic and then the anomalous Hall effect is observed. Below the TC of the Nb electrodes (~8.2 K), we observed a conductance reduction within the Nb superconducting energy gap voltage owing to the suppression of Andreev reflection by spin polarization in p-In0.96Mn0.04As. We evaluated the degree of spin polarization in p-In0.96Mn0.04As experimentally by comparing the measured differential conductance with that obtained with Strijkers' model extended for spin-polarized Andreev reflection including the inverse proximity effect. Consequently, the P value extracted experimentally for p-In0.96Mn0.04As at 0.5 K was 0.795 assuming Z = 0.

We report magnetic domain wall (DW) resistance in epitaxial films of FePd. When equal numbers of Fe and Pd atoms are present, this material forms an ordered structure with alternating crystal planes of Fe and Pd. We prepared films enriched with Pd to varying degrees, gradually degrading this structure. As might be expected, this increased the electrical resistivity of the films by introducing extra defects that can scatter electrons. However, unexpectedly, the additional resistance arising from the ~10 nm thick DWs rose as a proportion of the overall resistivity, roughly doubling when halving the degree of chemical ordering—as determined from x-ray diffraction measurements—within the films. These data can be used to infer a rise in the spin polarization of the current flowing in the layers when extra Pd atoms are introduced. On the other hand, a separate measurement of spin polarization using a superconducting point contact technique that is insensitive to electron scattering revealed no changes as extra Pd was introduced. We conclude that Pd atoms scatter electrons of one spin far more strongly than the other, suggesting a possible means of producing highly spin-polarized currents for use in spintronic devices.

The quantitative analysis of spin-polarized photoemission data is discussed. An angle-resolving photoelectron spectrometer equipped with a three-dimensional (3D) spin polarimeter produces complete data sets consisting of photoemission intensities as well as spin asymmetry curves for three orthogonal vector components. In a two-step fitting routine, the photoemission spectrum is first dissected into individual peaks and background. Assigning trial spin polarization vectors to each of them, the asymmetry curves can be modeled until the best fit is reached. This procedure is crucial when analyzing strongly overlapping peaks or weak signals sitting on a large unpolarized background, especially in the presence of non-collinear spins. It is robust against strong intensity variations due to matrix element effects because it references the spin polarization contribution of each band to the measured peak intensity. The method is applied to 2D systems where spin–orbit effects lead to spin splittings and complex momentum-dependent spin structures. Presented case studies include surface alloys of Bi and Pb on Ag(111) that show a giant Rashba effect.

The atomic and electronic structures at the apex of W tips were studied by means of field ion microscopy and field emission microscopy, before and after the thermal deposition of a 5 nm Fe film. Two geometries of W tip, a conventional hemi-spherical type and a chisel (flat needle) type, were prepared. The hemispherical and the chisel W tips had a 110 direction parallel and perpendicular to the tip axis, respectively. The coated Fe films were found to be most likely in a non-crystalline phase, and to have a lower work function leading to a drastic change in electron emission from the apexes. The spin-polarization vectors of field-emitted electrons from these Fe/W tips were investigated with a Mott detector with a rotatable mechanism of tips. A similar absolute value of the spin-polarization vector was obtained for each Fe/W, while the direction of the spin-polarization vector was dependent on the shape of the apex. The angle from the tip axis was θ=45° for the hemispherical apex and θ=66° for the chisel apex. A spin-polarized scanning tunneling microscopy setup with a rotation mechanism of such Fe/W tips made it possible to detect both the in-plane and the out-of-plane spin component of a sample magnetization.

We present an analysis of the relativistic electronic structure of the 1×1 H/W(110) surface. Our calculations reproduce in detail the experimentally determined Fermi surface and spin polarization of the surface electron states. A projected spin-polarized density of states is defined in order to simulate the photoemission spectra exhibiting very good agreement with existing spin-resolved measurements. Our calculations confirm that the spin-split states, S1 and S2, are approximately circularly spin polarized with respect to the high-symmetry point . Moreover, we present the precise shape and magnitude of the spin polarization of the spin–orbit split S1 and S2 states, through the entire Brillouin zone.

The spin polarization (P) of high-density InSb two-dimensional electron systems (2DESs) has been measured using both parallel and tilted magnetic fields. P is found to exhibit a superlinear increase with the total field B. This P-B nonlinearity results in a difference in spin susceptibility between its real value Xs and Xgm ~ m*g*(m* and g* are the effective mass and g factor, respectively) as routinely used in experiments. We demonstrate that such a P-B nonlinearity originates from the linearly P-dependent g* due to the exchange coupling of electrons rather than from the electron correlation as predicted for the low-density 2DES., 14 pages, 4 figures

Cylindrically symmetric electron beams in spin polarization are reported for the first time. They are shown to be the eigen states of total angular momentum in the $z$ direction. But they are neither the eigen states of spin nor the eigen states of orbital angular momentum in that direction.

We investigated the non-contact Andreev reflection of the normal-conductor / superconductor junction as a tool for spin polarization measurement of ferromagnetic metals. The conductance due to the Andreev reflection is obtained by numerically solving the corresponding one-dimensional Bogoliubov-de Gennes equation with use of the recursion-transfer-matrix method. We showed that the conductance suppression due to the exchange splitting of conduction band in ferromagnets. We also derived the analytical expression of the zero-bias conductance due to the Andreev reflection through the square barrier which agrees well with the exact numerical values.

We construct a novel scattering theory to investigate magnetoelectrically induced spin polarizations. Local spin polarizations generated by electric currents passing through a spin-orbit coupled mesoscopic system are measured by an external probe. The electrochemical and spin-dependent chemical potentials on the probe are controllable and tuned to values ensuring that neither charge nor spin current flow between the system and the probe, on time-average. For the relevant case of a single-channel probe, we find that the resulting potentials are exactly independent of the transparency of the contact between the probe and the system. Assuming that spin relaxation processes are absent in the probe, we therefore identify the local spin-dependent potentials in the sample at the probe position, and hence the local current-induced spin polarization, with the spin-dependent potentials in the probe itself. The statistics of these local chemical potentials is calculated within random matrix theory. While they vanish on spatial and mesoscopic average, they exhibit large fluctuations, and we show that single systems typically have spin polarizations exceeding all known current-induced spin polarizations by a parametrically large factor. Our theory allows to calculate quantum correlations between spin polarizations inside the sample and spin currents flowing out of it. We show that these large polarizations correlate only weakly with spin currents in external leads, and that only a fraction of them can be converted into a spin current in the linear regime of transport, which is consistent with the mesoscopic universality of spin conductance fluctuations. We numerically confirm the theory., Comment: Final version; a tunnel barrier between the probe and the dot is considered. To appear in 'Nanotechnology' in the special issue on "Quantum Science and Technology at the Nanoscale"

Synopsis We investigate the effects of using an ab initio complex optical potential to calculate the spin polarization parameters S, T and U for spin polarized electrons elastically scattering from the heavy noble gases at intermediate energies. We carry out our calculations within the framework of the Dirac scattering equations which include the spin of the electron explicitly. The real part of the optical potential represents the polarization of the target by the incident electron while the imaginary part takes into account the loss of incident flux into open inelastic channels. The values of the STU parameters for scattering angles near the minima of the differential cross sections are very sensitive to the details of the theoretical model.

Positive magnetoresistance (PMR) of a silicon MOSFET in parallel magnetic fields B has been measured at high electron densities n >> n_c where n_c is the critical density of the metal-insulator transition (MIT). It turns out that the normalized PMR curves, R(B)/R(0), merge together when the field is scaled according to B/B_c(n) where B_c is the field in which electrons become fully spin polarized. The values of B_c have been calculated from the simple equality between the Zeeman splitting energy and the Fermi energy taking into account the experimentally measured dependence of the spin susceptibility on the electron density. This extends the range of validity of the scaling all the way to a deeply metallic regime far away from MIT. The subsequent analysis of PMR for low n >~ n_c demonstrated that the merging of the initial parts of curves can bee achieved only with taking into account the temperature dependence of B_c. It is also shown that the shape of the PMR curves at strong magnetic fields is affected by a crossover from a purely two-dimensional (2D) electron transport to a regime where out-of-plane carrier motion becomes important (quasi-three-dimensional regime)., 5 pages, including 6 figures; misprints corrected; Europhys. Lett. (in press)

A generalized BTK model for charge transport in ferromagnet/superconductor point contacts can be used to estimate spin polarization in a ferromagnet. We demonstrate the effect that an applied magnetic field or the spontaneous magnetization field has on the reliability of the model parameters as fitted from conductance experiments.

Using circularly polarized synchrotron radiation, the 5p pi ionization of HI molecules is studied by means of angle-resolved photoelectron spin polarization spectroscopy. The energy dependences of the dynamical photoionization parameters are obtained and compared with an ab initio calculation of Raseev et al. (1987) and the corresponding data for the xenon atom. Angular distributions of the polarization component A( Theta ) yield complete parameter sets. A strong influence of electronic autoionization is observed and analysed in terms of partial contributions using the additional information contained in the polarization results.