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

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

8 Dec 2008

Volume 93, Issue 23, Articles (23xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 93, 231101 (2008); http://dx.doi.org/10.1063/1.3040686 (3 pages)

Mads Brøkner Christiansen, Anders Kristensen, Sanshui Xiao, and Niels Asger Mortensen
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds
FREE

Composition dependence of magnetocaloric effect in Sm1−xSrxMnO3(x = 0.3–0.5)

A. Rebello and R. Mahendiran

Appl. Phys. Lett. 93, 232501 (2008); http://dx.doi.org/10.1063/1.3040698 (3 pages) | Cited 27 times

Online Publication Date: 8 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigated magnetic and magnetocaloric properties in Sm1−xSrxMnO3(x = 0.3–0.5). We report a magnetic field-driven first-order metamagnetic transition in the paramagnetic state in x = 0.4 and 0.5 and a second-order transition in x = 0.3. The highest magnetic entropy (−ΔSm = 1.41 J/mol K for ΔH = 5 T at T = 125 K) that occurs in x = 0.4 is associated with the metamagnetic transition resulting from the field-induced growth and coalescence of ferromagnetic nanoclusters pre-existing in the paramagnetic state. Our results suggest that manganites with intrinsic nanoscale phase separation can be exploited for magnetic refrigeration.
Show PACS
75.47.Lx Magnetic oxides
65.40.gd Entropy
75.47.Gk Colossal magnetoresistance
FREE

Electric detection of ferromagnetic resonance in single crystal iron film

Xiong Hui, A. Wirthmann, Y. S. Gui, Y. Tian, X. F. Jin, Z. H. Chen, S. C. Shen, and C.-M. Hu

Appl. Phys. Lett. 93, 232502 (2008); http://dx.doi.org/10.1063/1.3029744 (3 pages) | Cited 5 times

Online Publication Date: 8 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report electric detection of ferromagnetic resonance (FMR) in epitaxially grown single crystal iron film through microwave photovoltage generation technique. The experimental results agree well with the established theory about FMR in iron films, showing excellent extendability of such a technique onto different ferromagnets as an effective way to study magnetocrystalline anisotropy and spin excitations. Furthermore, the information about the phase of magnetization precession is implicated in the lineshape of photovoltage, which makes it possible to probe in details into magnetic phase dynamics that is of significance for devising spintronic devices.
Show PACS
76.50.+g Ferromagnetic, antiferromagnetic, and ferrimagnetic resonances; spin-wave resonance
75.30.Gw Magnetic anisotropy
75.70.Ak Magnetic properties of monolayers and thin films
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
75.40.Gb Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.)
FREE

Atomic ordering and magnetic properties in the Ni45Co5Mn36.7In13.3 metamagnetic shape memory alloy

W. Ito, M. Nagasako, R. Y. Umetsu, R. Kainuma, T. Kanomata, and K. Ishida

Appl. Phys. Lett. 93, 232503 (2008); http://dx.doi.org/10.1063/1.3043456 (3 pages) | Cited 22 times

Online Publication Date: 9 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effects of chemical order on the phase stability and magnetic properties of the metamagnetic shape memory alloy Ni45Co5Mn36.7In13.3 were investigated. Alloys quenched from the B2 and L21 phase regions were found to transform to the L10 and 6M martensite phases, respectively. For alloys quenched from the B2 region the martensitic transformation starting temperature is about 80 K higher than that for alloys quenched from the L21 region. The Curie temperature of the parent phase and the magnetization of the martensite phase were both lower for the alloy quenched from the B2 region than those for the alloy quenched from L21 region.
Show PACS
81.30.Kf Martensitic transformations
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
81.30.Hd Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder
64.70.kd Metals and alloys
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.30.Cr Saturation moments and magnetic susceptibilities
FREE

Ferromagnetic structurally disordered ZnO implanted with Co ions

K. Potzger, Shengqiang Zhou, Qingyu Xu, A. Shalimov, R. Groetzschel, H. Schmidt, A. Mücklich, M. Helm, and J. Fassbender

Appl. Phys. Lett. 93, 232504 (2008); http://dx.doi.org/10.1063/1.3040696 (3 pages) | Cited 10 times

Online Publication Date: 10 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present superparamagnetic clusters of structurally highly disordered Co–Zn–O created by high fluence Co ion implantation into ZnO (0001) single crystals at low temperatures. This secondary phase cannot be detected by common x-ray diffraction but is observed by high-resolution transmission electron microscopy. In contrast to many other secondary phases in a ZnO matrix, it induces low-field anomalous Hall effect and is thus a candidate for magnetoelectronics applications.
Show PACS
61.72.uj III-V and II-VI semiconductors
75.20.-g Diamagnetism, paramagnetism, and superparamagnetism
75.50.Tt Fine-particle systems; nanocrystalline materials
75.50.Pp Magnetic semiconductors
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
61.46.Df Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots)
FREE

Coherent control of magnetization precession in ferromagnetic semiconductor (Ga,Mn)As

E. Rozkotová, P. Němec, N. Tesařová, P. Malý, V. Novák, K. Olejník, M. Cukr, and T. Jungwirth

Appl. Phys. Lett. 93, 232505 (2008); http://dx.doi.org/10.1063/1.3046718 (3 pages) | Cited 8 times

Online Publication Date: 12 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report single-color, time-resolved magneto-optical measurements in ferromagnetic semiconductor (Ga,Mn)As. We demonstrate coherent optical control of the magnetization precession by applying two successive ultrashort laser pulses. The magnetic field and temperature dependent experiments reveal the collective Mn-moment nature of the oscillatory part of the time-dependent Kerr rotation, as well as contributions to the magneto-optical signal that are not connected with the magnetization dynamics.
Show PACS
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
78.20.Ls Magneto-optical effects
78.47.-p Spectroscopy of solid state dynamics
75.50.Pp Magnetic semiconductors
FREE

Current-induced flip-flop of magnetization in magnetic tunnel junction with perpendicular magnetic layers and polarization-enhancement layers

Woojin Kim, Taek Dong Lee, and Kyung-Jin Lee

Appl. Phys. Lett. 93, 232506 (2008); http://dx.doi.org/10.1063/1.3046729 (3 pages) | Cited 3 times

Online Publication Date: 12 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We performed a micromagnetic investigation of current-induced magnetization switching in perpendicular magnetic tunnel junctions with polarization-enhancement layers. The pinned layer with a polarization-enhancement layer can be excited and eventually reverses at a current density lower than the value theoretically expected from that without a polarization-enhancement layer. The reversal results in continuous flip-flops of magnetizations as long as the current is applied. The flip-flop occurs at only one current polarity, caused by the precession amplification in polarization-enhancement layer. In order to prevent the unwanted flip-flop, the perpendicular anisotropy of the pinned layer must be severalfold larger than that of the free layer.
Show PACS
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.60.Jk Magnetization reversal mechanisms
85.75.Dd Magnetic memory using magnetic tunnel junctions
FREE

Room temperature ferromagnetism in carbon-implanted ZnO

Shengqiang Zhou, Qingyu Xu, Kay Potzger, Georg Talut, Rainer Grötzschel, Jürgen Fassbender, Mykola Vinnichenko, Jörg Grenzer, Manfred Helm, Holger Hochmuth, Michael Lorenz, Marius Grundmann, and Heidemarie Schmidt

Appl. Phys. Lett. 93, 232507 (2008); http://dx.doi.org/10.1063/1.3048076 (3 pages) | Cited 64 times

Online Publication Date: 12 December 2008

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Unexpected ferromagnetism has been observed in carbon doped ZnO films grown by pulsed laser deposition [ H. Pan et al., Phys. Rev. Lett. 99, 127201 (2007) ]. In this letter, we introduce carbon into ZnO films by ion implantation. Room temperature ferromagnetism has been observed. Our analysis demonstrates that (1) C-doped ferromagnetic ZnO can be achieved by an alternative method, i.e., ion implantation, and (2) the chemical involvement of carbon in the ferromagnetism is indirectly proven.
Show PACS
75.50.Pp Magnetic semiconductors
75.50.Dd Nonmetallic ferromagnetic materials
81.20.-n Methods of materials synthesis and materials processing
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close