The topological features of the formation of (Co
40
Fe
40
B
20
)
15
(LiNbO
3
)
85
composite films deposited by ion-beam method on a metal electrode Cr/Cu/Cr has been investigated. The presence of a ...dielectric layer between the upper Cr layer and the CoFe–LiNbO
3
film with a thickness of
d
ox
≈ 15 nm has been established. The difference in the size of granules near the amorphous layer and in the volume of the film has been shown. A model of the formation of (Co
40
Fe
40
B
20
)
x
(LiNbO
3
)
100 –
x
nanocomposite film at the initial stage of growth has been proposed. It has been shown that the formation of α-LiNbO
3
layer on the chrome metal film surface is possible with the realization of island and layer-by-layer growth mechanisms for various phases of the composite.
The effect of oxygen and water vapor in a sputtering chamber during the deposition of thin-film (Co
40
Fe
40
B
20
)
x
(LiNbO
3
)
100 –
x
nanocomposites on the electrical properties of the ...heterogenous system is investigated. It is found that the resistivity of (Co
40
Fe
40
B
20
)
x
(LiNbO
3
)
100 –
x
nanocomposites increases significantly with the partial pressure of reactive gases (oxygen and water vapor). A noticeable shift of the percolation threshold towards higher values of the metal phase volume concentration, which is observed in the plane of the film and in the perpendicular direction during the synthesis of composites with the addition of reactive gases, is attributed to the increase in the volume concentration of the dielectric phase. It is found that the percolation threshold for the measurements in the geometry perpendicular to the plane of the film is characterized by a much lower concentration of the Co
40
Fe
40
B
20
alloy atoms than that for the measurements in the plane of the film, which is associated with an elongated shape of granules in the film growth direction and the effects of Coulomb blockade suppression by a high transverse electric field.
Multilayer films (In
2
O
3
/SnO
2
)
69
are obtained via ion-beam sputtering. The effect vacuum heat treatment in the range of room temperature to 600°C has on the structure and electrical properties ...is studied. It is found that the structures obtained with different thicknesses of the In
2
O
3
/SnO
2
bilayer are stable up to a heat treatment temperature of 400°С. Raising the temperature to 600°C alters the sign of the coefficient of temperature resistance from negative to positive.
The effect of oxygen and water vapor in a sputtering chamber during the deposition of thin-film (Co.sub.40Fe.sub.40B.sub.20).sub.x(LiNbO.sub.3).sub.100 -.sub.x nanocomposites on the electrical ...properties of the heterogenous system is investigated. It is found that the resistivity of (Co.sub.40Fe.sub.40B.sub.20).sub.x(LiNbO.sub.3).sub.100 -.sub.x nanocomposites increases significantly with the partial pressure of reactive gases (oxygen and water vapor). A noticeable shift of the percolation threshold towards higher values of the metal phase volume concentration, which is observed in the plane of the film and in the perpendicular direction during the synthesis of composites with the addition of reactive gases, is attributed to the increase in the volume concentration of the dielectric phase. It is found that the percolation threshold for the measurements in the geometry perpendicular to the plane of the film is characterized by a much lower concentration of the Co.sub.40Fe.sub.40B.sub.20 alloy atoms than that for the measurements in the plane of the film, which is associated with an elongated shape of granules in the film growth direction and the effects of Coulomb blockade suppression by a high transverse electric field.
A series of semi-inclusive deep-inelastic scattering measurements on deuterium, helium, neon, krypton, and xenon targets has been performed in order to study hadronization. The data were collected ...with the HERMES detector at the DESY laboratory using a 27.6 GeV positron or electron beam. Hadron multiplicities on nucleus
A relative to those on the deuteron,
R
A
h
, are presented for various hadrons (
π
+
,
π
−
,
π
0
,
K
+
,
K
−
,
p, and
p
¯
) as a function of the virtual-photon energy
ν, the fraction
z of this energy transferred to the hadron, the photon virtuality
Q
2
, and the hadron transverse momentum squared
p
t
2
. The data reveal a systematic decrease of
R
A
h
with the mass number
A for each hadron type
h. Furthermore,
R
A
h
increases (decreases) with increasing values of
ν (
z), increases slightly with increasing
Q
2
, and is almost independent of
p
t
2
, except at large values of
p
t
2
. For pions two-dimensional distributions also are presented. These indicate that the dependences of
R
A
π
on
ν and
z can largely be described as a dependence on a single variable
L
c
, which is a combination of
ν and
z. The dependence on
L
c
suggests in which kinematic conditions partonic and hadronic mechanisms may be dominant. The behaviour of
R
A
π
at large
p
t
2
constitutes tentative evidence for a partonic energy-loss mechanism. The
A-dependence of
R
A
h
is investigated as a function of
ν,
z, and of
L
c
. It approximately follows an
A
α
form with
α
≈
0.5
–
0.6
.
A recoil detector will be installed surrounding the internal gas target of the HERMES experiment at DESY. The recoil detector will improve the selection of exclusive events by a direct measurement of ...the momentum and track direction of the recoiling particle. The innermost layer of this recoil detector is a new silicon strip detector (SSD). Since Monte Carlo simulations predict proton momenta as low as 100 MeV/c, the SSD will be placed inside the HERA vacuum. A new setup of the electronics enables a dynamic range from below 4 fC at a signal-to-noise ratio of 6.8 up to 270 fC. In this paper, the assembly of the first module and the final setup within the HERMES experiment will be presented. Results from charge-injection tests of a prototype module are given.
The exclusive electroproduction of π+ mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off an internal hydrogen gas target. ...The virtual-photon cross sections were measured as a function of the Mandelstam variable t and the squared four momentum −Q2 of the exchanged virtual photon. A model calculation based on Generalized Parton Distributions is in fair agreement with the data at low values of |t| if power corrections are included. A model calculation based on the Regge formalism gives a good description of the magnitude and the t and Q2 dependences of the cross section.
Single-spin asymmetries have been measured for semi-inclusive electroproduction of π+, π−, π0 and K+ mesons in deep-inelastic scattering off a longitudinally polarised deuterium target. The ...asymmetries appear in the distribution of the hadrons in the azimuthal angle φ around the virtual photon direction, relative to the lepton scattering plane. The corresponding analysing powers in the sinφ moment of the cross section are 0.012±0.002(stat.)±0.002(syst.) for π+, 0.006±0.003(stat.)±0.002(syst.) for π−, 0.021±0.005(stat.)±0.003(syst.) for π0 and 0.013±0.006(stat.)±0.003(syst.) for K+. The sin2φ moments are compatible with zero for all particles.
PDF
