6 research outputs found
Point Contact Spin Spectroscopy of Ferromagnetic MnAs Epitaxial Films
We use point contact Andreev reflection spin spectroscopy to measure the
transport spin polarization of MnAs epitaxial films grown on (001) GaAs. By
analyzing both the temperature dependence of the contact resistance and the
phonon spectra of lead acquired simultaneously with the spin polarization
measurements, we demonstrate that all the point contacts are in the ballistic
limit. A ballistic transport spin polarization of approximately 49% and 44% is
obtained for the type A and type B orientations of MnAs, respectively. These
measurements are consistent with our density functional calculations, and with
recent observations of a large tunnel magnetoresistance in MnAs/AlAs/(Ga,Mn)As
tunnel junctions.Comment: 5 Figure
High performance single crystal OFETs based on two dithiophene-tetrathiafulvalene (DT-TTF) polymorphs
Time sequence and time scale of intermediate mass fragments emission
Semiperipheral collisions in the 124Sn+64Ni reaction at 35MeV/nucleon were studied using the forward part of
the Charged Heavy IonMass and Energy ResolvingArray. Nearly completely determined ternary events involving
projectilelike fragments (PLF), targetlike fragments (TLF), and intermediatemass fragments (IMF) were selected.
A new method of studying the reaction mechanism, focusing on the analysis of the correlations between relative
velocities in the IMF+PLF and IMF+TLF subsystems, is proposed. The relative velocity correlations provide
information on the time sequence and time scale of the neck fragmentation processes leading to production of
IMFs. It is shown that the majority of light IMFs are produced within 40–80 fm/c after the system starts to
reseparate. Heavy IMFs are formed at times of about 120 fm/c or later and can be viewed as resulting from
two-step (sequential) neck rupture processes