GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Document type
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Particle size dependence of magnetic behavior and giant magnetoresistance in granular Fe—Ag films (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 998-1002 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have studied the magnetic, and magnetotransport properties of a metallic granular FexAg1−x alloys (x=0–0.45), fabricated by using an electron-beam coevaporation technique. Observations with a transmission electron microscope confirmed that these alloys consist of small Fe particles embedded in an Ag matrix. Based on the superparamagnetic theory, the average number N of iron atoms in a particle, ranging from 102 to 816 as x=0.05–0.21, and, therefore, the average granular size of iron particles, has been determined by simulating the magnetization curves above the blocking temperature. At 1.5 K, the average magnetic moment of iron particles has been found to be reduced as N〈400. At a low temperature, the temperature dependence of magnetization for samples with x≥0.21 follows Bloch's T3/2 law. Moreover, giant magnetoresistance (GMR) has been observed at 1.5 K. Its magnitude is sensitively dependent on the size and density of the magnetic entities. As the granular radius is in the region of 8–13 A(ring), the GMR value is about 50%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357785
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Magnetic properties and magnetoresistance in granular Fe-Cu alloys (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 2986-2990 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The structural, magnetic, and electrotransport properties of a metallic granular FexCu1−x alloys (x=0–0.35) were studied. These alloys were fabricated by using a coevaporation technique with an extremely high deposition rate. Observations by transmission electron microscope confirmed that these alloys consist of small Fe particles embedded in a Cu matrix. The ferromagnetic-superparamagnetic transition occurs at the blocking temperature. The blocking temperature TB, dependent on the atomic fraction x of Fe, is in a range of 80–300 K as x=0.10–0.22. Above TB, the Fe particles exhibit superparamagnetic relaxation. Their magnetic behavior can be understood based on superparamagnetic theory. At low temperature, the temperature dependence of magnetization has shown that the magnetic behavior of Fe particles in granular Fe-Cu alloys evolves from three- to two-dimensional ferromagnetism as the Fe concentration is reduced. Moreover, large magnetoresistance in the granular Fe-Cu alloys was observed at 77 K. Its magnitude is affected by the size and density of the magnetic entities, which can be controlled by varying the Fe concentration in the Cu matrix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358505
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Optical and magneto-optical properties of NdTbFeCo thin films (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 4498-4502 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Three series of NdxTbyFe1−x−y−zCoz films have been fabricated for their potential application in magneto-optical recording: (i) x=0–0.20, Tb was adjusted so that the coercivity at room temperature was 5–10 kOe; (ii) x+y=0.28–0.32 with x in the range of 0 to 0.25; and (iii) x+y=0.21–0.23 with x in the range of 0 to 0.17. These films have been characterized both optically and magneto-optically by Kerr hysteresis trace, variable angle of incidence ellipsometry, and normal angle of incidence Kerr spectroscopy. From these measurements, the optical constants (n and k), magneto-optical constants (Q1 and Q2), and maximum possible figure of merit (FOM) have been determined at wavelengths of 405, 546, and 633 nm. Results demonstrate that the magneto-optical behavior of NdTbFeCo films is sensitive to the concentration of both Nd and Tb in the film. For samples in the series (i), the addition of Nd into TbFeCo alloys was shown not to enhance their magneto-optic behavior at the short wavelengths. For samples in the series (ii) and (iii), the substitution of Nd improves the magneto-optical performance greatly at blue light. But at red and green wavelengths it has little effect on the magneto-optical properties in samples in the series (iii) or degrades in samples in the series (ii). The maximum enhancement in the FOM is about 25% at x∼10% for blue light. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.363430
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Structure and magnetic properties of MnBiDy(Sm) permanent magnetic films (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 1178-1183 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have studied crystal texturing and magnetic properties of MnBiDy(Sm) permanent magnetic films, with thicknesses varying from 60 to 1200 nm, fabricated by the thermal coevaporation method and subsequently annealed in a vacuum oven at temperatures ranging from 350–425 °C. X-ray diffraction analysis has shown that the samples exhibit low-temperature phase MnBi with a NiAs-type structure when the thicknesses of the samples are less than 250 nm. When the thicknesses are larger than 250 nm, however, the Bi3Mn2 phase also appears. Magnetic measurements have revealed that saturation magnetization σs=46–78 emu/g, residual magnetic induction Br=3.2–7.3 kGs, remnant magnetization ratio r=0.64–0.98, intrinsic coercive force Hc=2.2–7.3 kOe, and magnetic energy product (BH)m=3.33–14.3 MGOe. We have also found that Hc depends on the thickness of the sample, and reaches a maximum when the thickness d=400 nm. The origin of the coercive force may be understood by the nucleation and growth of reverse magnetic domains when d〈150 nm but by domain rotation when d(approximately-greater-than)600 nm. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.358982
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Thermal cross-track cross talk in phase-change optical disk data storage (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 1214-1220 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have investigated the temperature distribution in land/groove phase-change optical disks. The incident beam is linearly polarized either parallel to track (E(parallel) polarization) or tangential to track (E⊥ polarization). Calculations have shown that temperature profiles in the medium are dependent on the wavelength of light, the state of polarization, the geometry of the grooved structure, and the multilayer stack. The temperature profiles are quite different between the land track and the groove track. Thermal cross-track cross talk from a land track to its neighboring groove tracks is higher than that from a groove track to its neighboring land tracks. The interaction between the E⊥ electric field and the grooved structure is mainly responsible for thermal cross-track cross talk. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.373806
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Noise and coupling in magnetic super-resolution media for magneto-optical readout (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 6323-6330 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Interfacial magnetic coupling, transient thermal response, and carrier and noise levels are investigated for two central aperture detection magnetic super-resolution disks. In one of the disks, the two magnetic layers are exchange-coupled, while in the other the coupling is of magneto-static nature. For the exchange-coupled disk, the coupling between the two magnetic layers is fairly strong, and the Kerr loop of the readout layer does not have a square shape. For the magneto-statically coupled disk, the strength of coupling depends on the nonuniformity of the magnetization of the storage layer. The readout layer has a square Kerr loop, but its perpendicular magnetization in the hot region under the focused spot has random orientation if the stray field from the storage layer is weak. This random orientation of magnetization within the readout layer gives rise to a high level of noise during readout. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.370133
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Magnetic properties of Ag/Ni multilayered films (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 3457-3461 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic properties of Ag/Ni multilayered films, prepared by the vacuum evaporation method, as a function of different thicknesses of Ni and Ag layers have been studied. It has been found that the magnetic moment of the Ni layer decreases greatly with increase of the thickness of the Ag layer. The temperature dependence of magnetization exhibits the features of Bloch's T3/2 law with a large value of the Bloch coefficient, B3/2, which also depends on the thickness of the Ag layer when the thickness of the Ni layer is fixed at 30 A(ring). These phenomena can be explained by means of the itinerant electron theory. Furthermore, the magnetic size effect of Ag/Ni multilayered films, such as a reduced Curie temperature as a function of the thickness of the Ni layer tNi and a linear dependence of magnetization on temperature for T〈175 K when tNi=10 A(ring), have been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350945
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Oscillatory interlayer magnetic exchange coupling in Ni80Fe20/Cr multilayer structures (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 72 (1992), S. 4250-4253 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The evidence of antiferromagnetic interlayer exchange coupling in Ni80Fe20 /Cr multilayers is reported. In Ni80Fe20/Cr multilayers, both the magnitude of the interlayer magnetic exchange coupling and the saturation magnetoresistance have been found to oscillate with the Cr spacer layer thickness with a period of about 13 A(ring). Moreover, a weaker absorption line above main line in ferromagnetic resonance spectrum for the antiferromagnetically coupling film with Cr layer thickness of 12 A(ring) has been observed in perpendicular geometry, and the strength of the antiferromagnetic coupling has been estimated to be about 0.017 erg/cm2 as well.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.352238
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Studies on the relation between the eigenvalue and enhancement of Kerr effect for magneto-optical materials (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 74 (1993), S. 6830-6839 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Based on the universal additivity law of the interference of light the following was achieved. (i) An analytic representation between the eigenvalue of the Kerr rotation angle θ0k and the enhanced θk for a double-layered film, θk=en1 θ0k, was obtained theoretically, where e is the enhancement factor and n1 is the refractive index of the dielectric medium. (ii) An analytic representation between θk and θ0k (θk=e013e123n2θ0k) of the trilayered film [bilayered transparent media and monolayered magneto-optical (MO) medium], was also obtained, where e013 and e123 are the enhancement factors: The calculated θk value is in good agreement with experimental results for e=1. In general, the theoretical calculation shows that θk is related to the thickness of the transparent media. Thus, if one wants to get an optimum value for θk, the thickness of the first transparent film layer (such as a glass substrate) must be selected carefully. It also shows that if the variation of the thickness of the glass substrate is 5 nm, θk could vary by 0.1° for MnBiCe films. (iii) The relation connecting θk with θ0k1 and θ0k2 for bilayered MO films has been theoretically studied, where θ0k1 and θ0k2 are the eigenvalues of the Kerr rotation angle of MO materials 1 and 2, respectively. Finally, θk for a Fe/Co film was calculated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.355083
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Experimental and theoretical investigations of laser-induced crystallization and amorphization in phase-change optical recording media (1997)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 82 (1997), S. 4183-4191 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We describe the numerical procedure for calculating three-dimensional profiles of temperature in a multilayer stack illuminated by a laser beam, and model the crystallization and amorphization kinetics for phase-change rewritable media. Experimental methods have been used to determine indirectly the probabilities of nucleation and growth for Ge2Sb2Te5 alloy. Some of the fundamental behaviors of phase-change erasable media, such as the crystallization of as-deposited amorphous phase, amorphization of supercooled liquid, and recrystallization of quenched amorphous phase, have been illustrated based on our three-dimensional temperature calculations and the model kinetics. The calculated transient reflectance behavior of as-deposited Ge2Sb2Te5 amorphous films in a single layer and in a quadrilayer stack, as well as the erasure behavior of Ge2Sb2Te5 alloy in a quadrilayer disk are in good agreement with experimental observations. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.366220
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...