Library

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report on the preparation and characterization of large scale periodic magnetic nanostructures designed as possible candidates for a future application in magnetic data storage technology. The nanostructures are prepared on glass substrates by UHV electron beam evaporation of Fe, Co, or Co/Pt onto periodically patterned photoresist masks followed by a lift-off of the photoresist. The preceding patterning process of the photoresist is achieved by using an interference lithography process in combination with subsequent selective etching. For the exposure of the photoresist, we use two different experimental setups with Ar ion lasers operating at wavelengths of 457 and 244 nm, respectively. This allows us to control diameter as well as distances between magnetic dots ranging between 300 and 3000 nm. The structural characterization of magnetic nanostructures is performed by electron microscopy as well as atomic force microscopy. Magnetic force microscopy along with additional image calculations based on dipole–dipole interaction between a magnetic tip and a magnetic dot allows for an interpretation of the magnetic properties of single magnetic dots. Accompanying work focuses on comparable nanostructures of smaller sized samples prepared by electron-beam lithography. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have performed inelastic neutron scattering measurements of the long-wavelength spin wave excitations of both ordered and disordered Fe72Pt28 single crystals below their critical temperatures, TC=510 and 375 K, respectively. The spin waves followed the expected E=Dq2 dependence, and the temperature-dependent spin stiffness D decreased as (T/TC)5/2, as expected for an isotropic ferromagnet. The extrapolated zero-temperature spin stiffness was D=98(4) meV A(ring)2 and 107(1) meV A(ring)2 for the disordered and ordered alloy, respectively. These values are significantly higher than the zero-temperature stiffness as determined by magnetization measurements.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 6098-6104 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An experimental technique is presented that allows determining the magnetization reversal and coercivity of magnetic-force microscopy (MFM) tips. An Ω-shaped current carrying gold ring with a radius of 2400 nm fabricated by electron-beam lithography and a lift-off technique is charged with a constant current in order to produce a magnetic stray field in the z direction that is detected by MFM. While an oscillating MFM tip is continuously raster scanned across the center of the current ring, an external magnetic field is applied in the z direction and increased in magnitude in order to reverse the tip magnetization during imaging. Thus, the corresponding changes in the measured image contrast exclusively describe the magnetization reversal and coercivity of the particular part of the tip that is used for imaging. We have investigated commercially available thin-film tips and we find that the hysteresis loops measured with MFM may be significantly different as compared to hysteresis loops measured by means of superconducting quantum interference magnetometry on the respective magnetic tip coatings of the same tip. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 86 (1999), S. 3410-3417 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We present experimental results on the characterization of commercially available magnetic force microscopy (MFM) thin film tips as a function of an external magnetic field. Well defined magnetic stray fields are produced using current carrying rings with radii ranging between 603 and 2369 nm fabricated by electron-beam lithography directly imaged by MFM. Treating the MFM tip as a point probe, the analysis of the image contrast as a function of both the magnetic stray field and the lift height allows for a quantitative determination of effective magnetic dipole and monopole moments of the tip as well as their imaginary location within the real physical tip. Our systematic study gives a quantitative relationship on how absolute values of the magnetic dipole and monopole moments and their location within the tip depend on a characteristic decay length of the z component of the magnetic field being detected. From this we can estimate the effective tip volume of the real physical thin film tip relevant in MFM imaging. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 63 (1988), S. 3499-3502 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have investigated the electronic structure of ordered Fe3Pt(001) by using spin- and angle-dependent photoemission with synchrotron radiation. The features in the spin-resolved energy distribution curves (SREDC's) can be understood in terms of the recent band-structure calculations for Fe3Pt. We have observed temperature-dependent changes in the EDC's which reveal some analogy to the 2γ-state model of Weiss. In our spin- and angle-resolved photoemission study of epitaxially grown ultrathin films of fcc Fe we observe major differences in its magnetic properties, depending on whether these films are grown on Cu(001) or on Cu3Au(001), i.e., substrates with small or large lattice constants.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 63 (1988), S. 3921-3923 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thermal expansion measurements as a function of temperature and magnetic field were carried out on Fe-Ni-Cr and Fe-Ni-Mn alloys. The magnetic contribution to the thermal expansion was determined with respect to the paramagnetic reference samples in the Fe-Ni-Cr and Fe-Ni-Mn series. We observe a general behavior that alloys which order ferromagnetically show a positive magnetovolume effect which persists to temperatures much higher than the Curie temperature, whereas in the case of antiferromagnetic ordering the magnetovolume effect is positive below temperatures slightly higher than the Néel temperature, and negative above it.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 61 (1987), S. 4103-4103 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic contribution to the specific heat Cm(T) of polycrystalline Ising-like spin glasses (SG) ScEr(1.05; 2.5 at. % Er) and ZnMn (195, 270 ppm Mn) has been measured in the temperature range 0.1〈T〈2.5 K, using a nonadiabatic heat pulse method. Cm(T) of the x-y–like SG CdMn (488 ppm Mn) has been measured on single crystals in external fields (Bex≤6 T) with Bex either ⊥ or (parallel) to the c axis. The data are compared with susceptibility measurements.1 For all samples the behavior of Cm(T) is similar to that in archetypal SG's. There is scaling and a linear dependence Cm(T) for T→0. The high-temperature data do not follow a simple 1/T or 1/T2 law. In contrast to the results from mean-field calculations for uniaxial systems we find no peaks in Cm(T). Yet, the relatively sharp maxima in Cm(T) at Tm of ScEr and ZnMn are close to the freezing temperatures T(parallel)g. In CdMn T⊥g from χ(T) lies well below Tm. The data for ScEr and ZnMn can be fitted within a two-level system model. For CdMn Cm is stronglydependent on Bex and shows anisotropic behavior. For Bex⊥ c (parallel to the easy axis) Cm(T,B) is SG-like for all fields and comparable to isotropic SG's. With increasing fields Tm shifts to higher temperatures and the slope in the linear range decreases. For Bex(parallel)c (hard direction) the behavior is quite different. For Bex 〈2 T the linear slope in Cm(T) and Tm are only weakly dependent on Bex. Increasing the field leads to a remarkable reduction of Cm(T) around Tm, and Cm(T) becomes nonlinear for T→0. This can be understood in terms of new mean-field calculations on anisotropic Ising-SG's by Usadel,2 who predicts a breakdown of the SG interactions in strong magnetic fields transverse to the easy axis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 6556-6558 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The magnetic and structural properties of Co100−xMnx alloys have been studied in the range 0≤x≤50 at. %. The structural phase diagram, which was revised with the aid of resistivity and thermal-expansion measurements for 4〈T〈1200 K, shows that the fcc↔hcp (γ↔ε) martensitic transformation temperature in Co-rich ferromagnetic CoMn alloys decreases progressively with increasing Mn content and vanishes at x(approximately-equal-to)32 at. %, rather than abruptly decreasing at a lower concentration as previously suggested. It is found that antiferromagnetic order, which occurs at x(approximately-greater-than)32 at. %, causes a large increase in the atomic volume, thereby preventing the structure from collapsing into the smaller volume hcp phase. The atomic volumes at 0 K of fcc Co and fcc Mn, which were determined by extrapolation, were found to be in good agreement with those obtained from band calculations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 6559-6561 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Fe-Cr-Mn alloys with 10 at. % Mn have similar structural and magnetic properties as Fe-Cr alloys, but have considerably higher Néel temperatures for the same Fe/(Fe+Cr) content ratio. When segregated, the high Néel temperatures of Fe-Cr-Mn alloys make it possible to investigate the magnetic nature of the Cr- and Fe-rich components. Resistivity and magnetization measurements show distinct features that correspond to a superposition of the properties of the individual segregated components.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 67 (1990), S. 5268-5270 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Co100−xMnx alloys form a system with competing magnetic interactions in the concentration range 25≤x≤42 at. %. They have ferromagnetic ground states in the fcc and hcp structures for 0≤x≤25 at. % and antiferromagnetic ground states in the fcc structure for 42≤x≤52 at. %. The thermal expansion of this alloy system has been measured between 4 and 1200 K and positive magnetovolume effects have been observed in samples that have both ferromagnetic and antiferromagnetic ground states.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...