APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue

27 Jun 2005

Volume 86, Issue 26, Articles (26xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 86, 263107 (2005); http://dx.doi.org/10.1063/1.1952585 (3 pages)

B. Yang, M. S. Marcus, D. G. Keppel, P. P. Zhang, Z. W. Li, B. J. Larson, D. E. Savage, J. M. Simmons, O. M. Castellini, M. A. Eriksson, and M. G. Lagally
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Noise subtraction in antiferromagnetically coupled magnetic recording media

Andreas Moser, Natacha F. Supper, Andreas Berger, David T. Margulies, and Eric E. Fullerton

Appl. Phys. Lett. 86, 262501 (2005); http://dx.doi.org/10.1063/1.1949725 (3 pages) | Cited 1 time

Online Publication Date: 20 June 2005

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have investigated, both experimentally and theoretically, the media noise of antiferromagnetically coupled (AFC) recording media. In particular, we have studied how the lower-layer magnetic properties affect the media noise of the composite system. We find that AFC media perform well even for intrinsically noisy lower layers, such as soft-magnetic Co or CoCr layers with high intergranular exchange coupling. To understand the experimentally observed behavior, we propose a new concept of noise subtraction in AFC magnetic systems, in which the noise of the lower layer is anticorrelated to and subtracts from the noise in the upper layers and acts as a low-pass magnetic filter of the magnetization state in the upper layer.
Show PACS
75.50.Ss Magnetic recording materials
75.50.Ee Antiferromagnetics
85.70.Kh Magnetic thin film devices: magnetic heads (magnetoresistive, inductive, etc.); domain-motion devices, etc.
75.70.Ak Magnetic properties of monolayers and thin films
75.30.Et Exchange and superexchange interactions
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects

Broadband spin dynamics of Permalloy rings in the circulation state

Xiaobin Zhu, Marek Malac, Zhigang Liu, Hui Qian, Vitali Metlushko, and Mark R. Freeman

Appl. Phys. Lett. 86, 262502 (2005); http://dx.doi.org/10.1063/1.1957107 (3 pages) | Cited 10 times

Online Publication Date: 20 June 2005

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The spin dynamics of the remanent state of circulating magnetization in micrometer-scale Permalloy rings is studied by broadband ferromagnetic resonance. A number of resonance modes are observed, depending upon the geometries of coupling the transient excitation to the ring and of magneto-optically monitoring the response. The two dominant modes involve precession with uniform phase around the ring, or in a circularly antisymmetric standing wave pattern with two nodes. Other magnetic normal modes are also excited but with much smaller amplitude.
Show PACS
75.40.Gb Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.)
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
76.50.+g Ferromagnetic, antiferromagnetic, and ferrimagnetic resonances; spin-wave resonance
75.50.Bb Fe and its alloys

Anisotropy dependence of irreversible switching in Fe/SmCo and FeNi/FePt exchange spring magnet films

Joseph E. Davies, Olav Hellwig, Eric E. Fullerton, J. S. Jiang, S. D. Bader, G. T. Zimányi, and Kai Liu

Appl. Phys. Lett. 86, 262503 (2005); http://dx.doi.org/10.1063/1.1954898 (3 pages) | Cited 39 times

Online Publication Date: 21 June 2005

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Magnetization reversal in exchange-spring magnet films has been investigated by a first-order reversal curve (FORC) technique and vector magnetometry. In Fe∕epitaxial-SmCo films, the reversal proceeds by a reversible rotation of the Fe soft layer, followed by an irreversible switching of the SmCo hard layer. The switching fields are clearly manifested by separate steps in both longitudinal and transverse hysteresis loops, as well as sharp boundaries in the FORC distribution. In FeNi∕polycrystalline-FePt films, particularly with thin FeNi, the switching fields are masked by the smooth and step-free major loop. However, the FORC diagram still displays a distinct onset of irreversible switching and transverse hysteresis loops exhibit a pair of peaks, whose amplitude is larger than the maximum possible contribution from the FeNi layer alone. This suggests that the FeNi and FePt layers reverse in a continuous process via a vertical spiral. The successive versus continuous rotation of the soft∕hard layer system is primarily due to the different crystal structure of the hard layer, which results in different anisotropies.
Show PACS
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.30.Gw Magnetic anisotropy
75.70.Cn Magnetic properties of interfaces (multilayers, superlattices, heterostructures)
75.60.Jk Magnetization reversal mechanisms

Direct observation of the magnetic-field-induced entropy change in Gd5(SixGe1−x)4 giant magnetocaloric alloys

Fèlix Casanova, Amílcar Labarta, Xavier Batlle, Francisco J. Pérez-Reche, Eduard Vives, Lluís Mañosa, and Antoni Planes

Appl. Phys. Lett. 86, 262504 (2005); http://dx.doi.org/10.1063/1.1968431 (3 pages) | Cited 26 times

Online Publication Date: 21 June 2005

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Direct observation of the entropy change in a first-order phase transition is obtained by using a differential scanning calorimeter in which the transition is field-induced under the application of an external magnetic field. This procedure enables direct evaluation of the magnetocaloric effect in materials showing first-order magnetostructural phase transitions. Results for Gd5(SixGe1−x)4 giant magnetocaloric alloys are reported. Calorimetric curves sweeping the field through the transition reveal a unusual increase of the entropy change with cycling. This increase is accounted for by considering both the structural and magnetic contributions to the total entropy change.
Show PACS
75.30.Sg Magnetocaloric effect, magnetic cooling
75.40.Cx Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.)
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
65.40.G- Other thermodynamical quantities

Room-temperature epitaxial growth of ferromagnetic Fe3Si films on Si(111) by facing target direct-current sputtering

T. Yoshitake, D. Nakagauchi, T. Ogawa, M. Itakura, N. Kuwano, Y. Tomokiyo, T. Kajiwara, and K. Nagayama

Appl. Phys. Lett. 86, 262505 (2005); http://dx.doi.org/10.1063/1.1978984 (3 pages) | Cited 21 times

Online Publication Date: 24 June 2005

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ferromagnetic Fe3Si thin films with an extremely smooth surface morphology can be epitaxially grown on Si(111) at room temperature by facing target direct-current sputtering. The epitaxial relationship is Fe3Si(111)‖Si(111) with Fe3Si[1math0]‖Si[math10]. By the application of the extinction rule of x-ray diffraction, the generated Fe3Si was confirmed to possess a B2 structure and not a DO3 one. The film showed a saturation magnetization value of 960 emu/cm3, which was slightly lower than that of bulk DO3-Fe3Si. It was observed that the magnetization easy axis was along the [1math0] direction in the film plane.
Show PACS
75.50.Dd Nonmetallic ferromagnetic materials
81.05.Cy Elemental semiconductors
68.55.A- Nucleation and growth
81.15.Cd Deposition by sputtering
68.55.-a Thin film structure and morphology
75.70.Ak Magnetic properties of monolayers and thin films
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
68.35.B- Structure of clean surfaces (and surface reconstruction)
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close