1,571 research outputs found
Relationships between leaf life span, leaf mass per area, and leaf nitrogen cause different altitudinal changes in leaf delta C-13 between deciduous and evergreen species
ArticleBOTANY-BOTANIQUE. 86(11):1233-1241 (2008)journal articl
Changes with altitude of the stand structure of temperate forests on Mount Norikura, central Japan
The original publication is available at www.springerlink.com.ArticleJOURNAL OF FOREST RESEARCH. 12(3):187-192(2007)journal articl
Theoretical analysis of magnetic coupling in sandwich clusters V_n(C_6H_6)_{n+1}
The mechanism of ferromagnetism stability in sandwich clusters
V(CH) has been studied by first-principles calculation and
model analysis. It is found that each of the three types of bonds between V and
benzene (Bz) plays different roles. V 3d orbital, extending along the
molecular axis, is weakly hybridized with Bz's HOMO-1 orbital to form the
-bond. It is quite localized and singly occupied, which contributes
1 to the magnetic moment but little to the magnetic coupling of
neighboring V magnetic moments. The in-plane d, d orbitals
are hybridized with the LUMO of Bz and constitute the -bond. This
hybridization is medium and crucial to the magnetic coupling though the
states have no net contribution to the total magnetic moment.
d, d and HOMO of Bz form a quite strong -bond to hold the
molecular structure but they are inactive in magnetism because their energy
levels are far away from the Fermi level. Based on the results of
first-principles calculation, we point out that the ferromagnetism stability is
closely related with the mechanism proposed by Kanamori and Terakura [J.
Kanamori and K. Terakura, J. Phys. Soc. Jpn. 70, 1433 (2001)]. However, the
presence of edge Bz's in the cluster introduces an important modification. A
simple model is constructed to explain the essence of the physical picture.Comment: 16 pages, 7 figure
Anomalous Hall voltage rectification and quantized spin-wave excitation induced by the simultaneous dc- and rf-current application in Ni81Fe19 wire
An anomalous Hall effect and rectification of a Hall voltage are observed by
applying a radio-frequency (rf) current through a single-layered ferromagnetic
wire located on a coplanar waveguide. The components of the magnetization
precession, both in and perpendicular to the plane, can be detected via the
Hall voltage rectification of the rf current by incorporating an additional
direct (dc) current. In this paper, we propose a phenomenological model, which
describes the time-dependent anisotropic magnetoresistance and time-dependent
planer Hall effect. The nonlinearity of the spin dynamics accompanied by
spin-waves as functions of rf and dc currents is also studied, as well as those
of the magnitude and orientation of the external magnetic field.Comment: 42 pages, 5 figures, submitte
One-Dimensional Organometallic V-Anthracene Wire and Its B-N Analogue: Efficient Half-Metallic Spin Filters
Using density functional theory, we have investigated the structural,
electronic and magnetic properties of infinitely periodic organometallic
vanadium-anthracene ([V_2Ant]_\infinity) and [V_4(BNAnt)_2]_\infinity(where
BNAnt is B-N analogue of anthracene) for their possible application in
spintronics. From our calculations, we find that one-dimensional
[V_2Ant]_\infinity and [V_4(BNAnt)_2]_\infinity wires exhibit robust
ferromagnetic half-metallic and metallic behavior, respectively. The finite
sized and clusters are also found to exhibit
efficient spin filter properties when coupled to graphene electrodes on either
side
Broadband ferromagnetic resonance of Ni81Fe19 wires using a rectifying effect
The broadband ferromagnetic resonance measurement using the rectifying effect
of Ni81Fe19 wire has been investigated. One wire is deposited on the center
strip line of the coplanar waveguide (CPW) and the other one deposited between
two strip lines of CPW. The method is based on the detection of the
magnetoresistance oscillation due to the magnetization dynamics induced by the
radio frequency field. The magnetic field dependences of the resonance
frequency and the rectification spectrum are presented and analytically
interpreted on the standpoint of a uniform magnetization precession model.Comment: 33pages, 8 figures. submitte
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