Faraday Rotation (faraday + rotation)

Distribution by Scientific Domains


Selected Abstracts


Photoinduced Faraday rotation in the magnetic semiconductor CdCr2Se4

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 4 2004
L. L. Golik
Abstract A growth of the excitonic peak in the absorption spectrum and an enhancement of the Faraday rotation band (approximately 50% of the linear effect value) were induced by intensive radiation of Nd3+ -laser (h, = 1.17 eV) in ferromagnetic phase of magnetic semiconductor CdCr2Se4. The photoinduced effects increased during a pumping pulse and also with growth of pump intensity. In studies of the non-linear Faraday rotation a change of the spectral band shape was observed along with the growth of the rotation angle. The observed effects can be explained by the screening of internal electric fields existing in CdCr2Se4 crystals by photoexcited charge carriers. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Nuclear field effect on the spin dynamics of electron localized on a donor in a single quantum well

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 7 2008
C. Testelin
Abstract We use photoinduced Faraday rotation (PFR) in presence of an applied magnetic field to study the spin dynamics of localized electrons. The sample is a CdTe/CdMgTe quantum well (QW) of width 80 Ĺ containing a layer of iodine donors at its center, with concentration 1011 cm,2. The spin polarization of donor-bound electrons is built via the optical polarization of donor-bound excitons, their hole spin relaxation, and their recombination. In a transverse (in-plane) magnetic field, PFR shows damped Larmor oscillations from which we deduce a 18 ns electron-spin decoherence time, and a transverse Landé factor of 1.29. In addition, for oblique optical incidence the electron-nuclei hyperfine interaction builds a nuclear spin polarization in presence of polarized electrons. This leads to the construction of an effective magnetic field, the Overhauser field, acting on the electronic spins. The Larmor frequency is then different for ,+ or ,, polarizations of the exciting light. The dependence of the phenomenon on the optical incidence allows the determination of the maximal Overhauser field, which is about 10 mT, at least two orders of magnitude weaker than for III-V semiconductors. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Figures of merit of magneto-optic spatial light modulators with magnetophotonic crystals

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 12 2007
K. Takahashi
Abstract This paper presents the simulated and measured results of two types of one dimensional magnetophotonic crystals (1-D MPC) with single cavity and dual cavity respectively for applcation to thin film type magneto-optic spatial light modulators (MOSLMs). The use of MPC is expected to be effective for thin film type MOSLM, because the apparent Faraday rotation is largely enhanced due to light localization in magnetic defect layer of MPC with a large number of periodic dielectric layers. The complex chracteristics of MPCs are discussed in this paper , Faraday rotation ,F, transmittance T, and figure of merit F = T sin(2,F). It is key point of finding optimal structure of MPC for application of MOSLM to use F, because the T decreased with increase of k, while Faraday rotation ,F increased, indicating that the enhancement of light modulation rate could be achieved by optimizing the figure of merit F defined by F , T ·sin2,F. The maximum F = 13.7 was obtained in dual cavity MPC, while F = 12.5 was obtained in single cavity MPC. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


YIG thin films for magneto-optical and microwave applications

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 12 2004
T. Boudiar
Abstract Thin films of Yttrium Iron Garnet (YIG) are grown by radio frequency magnetron non reactive sputtering system on quartz and Gadolinium Gallium Garnet (GGG) for optical applications or alumina substrates for microwave applications. A post deposition annealing is needed to obtain the crystallization of YIG films and the magnetic properties which are correlated with the magneto-optical properties. Their crystallographic, morphologic and magnetic properties are explored. The variation of Faraday rotation is studied versus the wavelength. For both optical substrates, quartz and GGG, results are comparable with the literature for bulk material. A microwave isolator was realized with YIG thin film on alumina substrate in a coplanar configuration. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


A model for polarised radio emission from Sgr A*

ASTRONOMISCHE NACHRICHTEN, Issue S1 2003
T. Beckert
Abstract The detection of circular polarisation in compact synchrotron sources provides new insights into magnetic field configurations and the low-energy population of electrons in relativistic jets. Conversion of linear to circular polarisation can be driven by Faraday rotation or turbulence in the source itself. A detailed model for the properties of Sgr A* in the galactic centre is presented. [source]