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

13 Sep 1999

Volume 75, Issue 11, pp. 1491-1646

Return to All Sections
back to top
RSS Feeds

Influence of target–substrate angle on the elemental concentration of c-axis YBa2Cu3O7−x thin films

D. E. Pugel and L. H. Greene

Appl. Phys. Lett. 75, 1589 (1999); http://dx.doi.org/10.1063/1.124763 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The thermalization processes in sputtering suggest a spatial dependence of elemental concentration in the sputter plume. A variety of analysis techniques demonstrate that c-axis films grown at angles which deviate from the standard off-axis geometry produce nominally YBa2Cu3O7−x in the bulk with dramatic changes in the surface morphology and deposition rate. In addition to the common materials characterization techniques of scanning electron microscopy, x-ray diffraction, transport measurements, and conventional Rutherford backscattering spectrometry (RBS), angle-dependent RBS is employed to probe surface inhomogeneities of films grown at target–substrate angles away from the standard off-axis position. © 1999 American Institute of Physics.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
74.72.-h Cuprate superconductors
81.15.Cd Deposition by sputtering
61.66.Bi Elemental solids
61.66.Dk Alloys
68.55.-a Thin film structure and morphology
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces

Ferromagnetic cluster behaviors and magnetoresistance in Ni-doped LaSrMnO3 systems

Ji-Wen Feng and Lian-Pin Hwang

Appl. Phys. Lett. 75, 1592 (1999); http://dx.doi.org/10.1063/1.124764 (3 pages) | Cited 16 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have studied the magnetic and magnetotransport properties of the perovskites La8Sr0.2Mn8Ni0.2O3 and La0.7Sr0.3Mn0.8Ni0.2O3. Ferromagnetic cluster behaviors have been observed. The most interesting feature is that the cluster-glass state exhibits both macroscopic insulator-like transport behavior and largely enhanced magnetoresistance (MR) at low temperature. Such a low-temperature MR is weakly temperature dependent. In particular, a low-temperature magnetoresistance ratio (Δρ/ρ0) as high as 60% has been found in La0.7Sr0.3Mn0.8Ni0.2O3. We attribute the low-temperature magnetotransport to the spin-dependent scattering inside the grains. © 1999 American Institute of Physics.
Show PACS
75.47.Gk Colossal magnetoresistance
72.20.My Galvanomagnetic and other magnetotransport effects
75.50.Dd Nonmetallic ferromagnetic materials
75.50.Lk Spin glasses and other random magnets
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects

Determination of critical current density in bulk melt-processed high temperature superconductors from levitation force measurements

A. A. Kordyuk, V. V. Nemoshkalenko, R. V. Viznichenko, W. Gawalek, and T. Habisreuther

Appl. Phys. Lett. 75, 1595 (1999); http://dx.doi.org/10.1063/1.124765 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A simple approach to describe levitation force measurements on bulk melt-processed high temperature superconductors was developed. A couple of methods to determine the critical current density Jc were introduced. The averaged a-b-plane Jc values for the field parallel to this plane were determined. The first and second levitation force hysteresis loops calculated with these Jc values coincide remarkably well with the experimental data. © 1999 American Institute of Physics.
Show PACS
74.72.-h Cuprate superconductors
74.25.Sv Critical currents
74.25.Ha Magnetic properties including vortex structures and related phenomena

Anisotropic electrical transport property in La4BaCu5O13+δ and La4BaCu4NiO13+δ epitaxial thin films

A. Venimadhav, P. Subramanya Herle, M. Vedawyas, C. Shivakumara, and M. S. Hegde

Appl. Phys. Lett. 75, 1598 (1999); http://dx.doi.org/10.1063/1.124766 (3 pages) | Cited 3 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Epitaxial films of La4BaCu5O13+δ and La4BaCu4NiO13+δ oxides are grown with a-b plane parallel to (100) of LaAlO3 and SrTiO3 by pulsed-laser deposition. The conductivity measurements performed along the c direction using LaNiO3 as the electrode show metallic behavior whereas they show semiconducting behavior in the a-b plane. Anisotropic transport property of these thin films is explained on the basis of nearly 180° connected Cu–O–Cu chains with an average Cu–O distance of 1.94 Å along the c direction and nearly 180° and 90° connected Cu–O–Cu chains in the a-b plane with short and long Cu–O distances ranging from 1.863 to 2.303 Å. YBa2Cu3O7−x has been grown along (00l) on La4BaCu5O13+δ and shows a Tc of 88 K. © 1999 American Institute of Physics.
Show PACS
74.72.-h Cuprate superconductors
74.78.-w Superconducting films and low-dimensional structures
74.10.+v Occurrence, potential candidates
74.25.F- Transport properties
81.15.Fg Pulsed laser ablation deposition
73.61.At Metal and metallic alloys
73.61.Le Other inorganic semiconductors

High-performance resin-bonded magnets produced from zinc metal-coated Sm2(Fe0.9Co0.1)17Nx fine powders

K. Noguchi, K. Machida, K. Yamamoto, M. Nishimura, and G. Adachi

Appl. Phys. Lett. 75, 1601 (1999); http://dx.doi.org/10.1063/1.124767 (3 pages)

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Fine powders of Sm2(Fe0.9Co0.1)17Nx (x = ∼ 3) with particle sizes (d) around 1 μm as coated with zinc metal produced via the photodecomposition of diethylzinc [Zn(C2H5)2], which still provided high remanence (Br) and coercivity (Hcj) values of ∼1.43 T and ∼0.85 MAm−1, were molded to compression-type resin bonded Zn/Sm2(Fe0.9Co0.1)17Nx magnets with density values of ∼6.33 g cm−3. By optimizing the preparation conditions such as grinding, surface coating, and molding for them, the highest maximum energy product of (BH)max = 186 kJm−3 for Hcj = 0.73 MAm−1 was recorded among all kinds of the Sm–Fe–N based magnets reported to date. Furthermore, the excellent aging behavior of the bonded Zn/Sm2(Fe0.9Co0.1)17Nx magnets was observed after standing in air at ∼393 K and the thermal coefficient for permanent magnet was evaluated to be α(Br) = −0.04% K−1. © 1999 American Institute of Physics.
Show PACS
75.50.Ww Permanent magnets
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
81.05.Bx Metals, semimetals, and alloys
81.20.Ev Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
81.10.Fq Growth from melts; zone melting and refining
75.50.Bb Fe and its alloys
81.40.Rs Electrical and magnetic properties related to treatment conditions
81.40.Cd Solid solution hardening, precipitation hardening, and dispersion hardening; aging

Thermal stability of longitudinal magnetic recording media

A. Moser, D. Weller, and M. F. Doerner

Appl. Phys. Lett. 75, 1604 (1999); http://dx.doi.org/10.1063/1.124768 (3 pages) | Cited 11 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thermal processes may limit the lifetime of stored data and ultimately the achievable areal density in magnetic recording. To quantify this important problem, we have studied a series of state-of-the-art thin film CoPtCr longitudinal recording media samples with thicknesses ranging between 5.5 and 13 nm. Static write/read tester experiments are used to measure the remanent coercivity of these films as a function of the applied magnetic field pulse width, which is varied in the range of nanoseconds to seconds. The data are analyzed in terms of an inverse slope parameter, 1/C, which in the framework of a Neel-Arrhenius model is equivalent to the familiar stability ratio EB/kBT. This ratio is then correlated with signal decay measurements, performed over a time range after writing of 2.8 s to ≈ 1 day. Both measurements are carried out at variable temperatures, T, between 300 and 390 K. The onset of strong signal decay in low density square wave bit patterns occurs when 1/C drops below about 36. © 1999 American Institute of Physics.
Show PACS
75.50.Ss Magnetic recording materials
75.70.Ak Magnetic properties of monolayers and thin films
75.50.Cc Other ferromagnetic metals and alloys
68.60.Dv Thermal stability; thermal effects
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close