15,630 research outputs found
Anomalous Nernst and Hall effects in magnetized platinum and palladium
We study the anomalous Nernst effect (ANE) and anomalous Hall effect (AHE) in
proximity-induced ferromagnetic palladium and platinum which is widely used in
spintronics, within the Berry phase formalism based on the relativistic band
structure calculations. We find that both the anomalous Hall ()
and Nernst () conductivities can be related to the spin Hall
conductivity () and band exchange-splitting () by
relations and
,
respectively. In particular, these relations would predict that the
in the magnetized Pt (Pd) would be positive (negative) since
the is positive (negative). Furthermore, both
and are approximately proportional to the
induced spin magnetic moment () because the is a linear
function of . Using the reported in the magnetized Pt and Pd, we
predict that the intrinsic anomalous Nernst conductivity (ANC) in the magnetic
platinum and palladium would be gigantic, being up to ten times larger than,
e.g., iron, while the intrinsic anomalous Hall conductivity (AHC) would also be
significant.Comment: Accepted for publication in the Physical Review
Essays on subjective expectations and mortality trends
This thesis consists of four chapters on two topics. The first topic, covered in chapter 2, 3, and 4, is about subjective expectations. Economists have long understood that expectations are important determinants of economic decisions. However, expectations are rarely observed. One way to overcome the problem is to elicit beliefs of individuals, or so-called subjective expectations, directly from survey questions. The three chapters study directly measured expectations on two important assets: housing and stock. Home ownership is very high in many countries and housing is typically the largest asset in most households' portfolios. Stock is often the major component of households' financial wealth. Chapter 2 investigates how house price expectations are related to macro and micro characteristics. Chapter 3 focuses on stock price expectations. Both chapters are based on panel data analysis of individual expectations at the micro level. Chapter 4 is also about house price expectations, but is from a macroeconomic perspective and relies on time series analysis of aggregate data. The second topic, discussed in Chapter 5, is about mortality trends. This chapter introduces a mortality forecasting model, which links mortality trends to trends in economic growth, and studies mortality dynamics for six developed countries
Quantum Theory of Orbital Magnetization and its Generalization to Interacting Systems
Based on standard perturbation theory, we present a full quantum derivation
of the formula for the orbital magnetization in periodic systems. The
derivation is generally valid for insulators with or without a Chern number,
for metals at zero or finite temperatures, and at weak as well as strong
magnetic fields. The formula is shown to be valid in the presence of
electron-electron interaction, provided the one-electron energies and wave
functions are calculated self-consistently within the framework of the exact
current and spin density functional theory.Comment: Accepted by Phys. Rev. Let
Unbalanced edge modes and topological phase transition in gated trilayer graphene
Gapless edge modes hosted by chirally-stacked trilayer graphene display
unique features when a bulk gap is opened by applying an interlayer potential
difference. We show that trilayer graphene with half-integer valley Hall
conductivity leads to unbalanced edge modes at opposite zigzag boundaries,
resulting in a natural valley current polarizer. This unusual characteristic is
preserved in the presence of Rashba spin-orbit coupling that turns a gated
trilayer graphene into a topological insulator with an odd number of
helical edge mode pairs.Comment: 5 pages, 4 figure
Quasi-particle random phase approximation with quasi-particle-vibration coupling: application to the Gamow-Teller response of the superfluid nucleus Sn
We propose a self-consistent quasi-particle random phase approximation (QRPA)
plus quasi-particle-vibration coupling (QPVC) model with Skyrme interactions to
describe the width and the line shape of giant resonances in open-shell nuclei,
in which the effect of superfluidity should be taken into account in both the
ground state and the excited states. We apply the new model to the Gamow-Teller
resonance in the superfluid nucleus Sn, including both the isoscalar
spin-triplet and the isovector spin-singlet pairing interactions. The strength
distribution in Sn is well reproduced and the underlying microscopic
mechanisms, related to QPVC and also to isoscalar pairing, are analyzed in
detail.Comment: 32 pages, 11 figures, 4 table
meson effects on neutron stars in the modified quark-meson coupling model
The properties of neutron stars are investigated by including meson
field in the Lagrangian density of modified quark-meson coupling model. The
population with meson is larger than that without
meson at the beginning, but it becomes smaller than that without meson
as the appearance of . The meson has opposite effects on
hadronic matter with or without hyperons: it softens the EOSes of hadronic
matter with hyperons, while it stiffens the EOSes of pure nucleonic matter.
Furthermore, the leptons and the hyperons have the similar influence on
meson effects. The meson increases the maximum masses of
neutron stars. The influence of on the meson effects
are also investigated.Comment: 10 pages, 6 figures, 4 table
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