257 research outputs found
Application of matrix product states to the Hubbard model in one spatial dimension
We investigate the application of matrix product states to the Hubbard model
in one spatial dimension with both of open and periodic boundary conditions. We
develop the variatinal method that the optimization of the variational
parameters is carried out locally and sequentially in the framework of matrix
product operators (MPO) by including the sign, due to the anti-commutation
relation of fermion operators, in the matrix element of MPO. The numerical
accuracy of the ground state energy is examined.Comment: 5 pages, 2 figure
Calculation of Thermodynamic Properties and Excitation Spectra of Anderson Model based on the Numerical Renormalization Group Method(Abstracts of Doctral Dissertations)
Role of NKT Cells in the Pathogenesis of NAFLD
Nonalcoholic fatty liver disease (NAFLD) is the most frequent chronic liver disease and shows various inflammatory changes in the liver. Among those inflammatory cells, natural killer T (NKT) cells are found to have a critical role during the disease progression. NKT cells may have a protective role at the early stage with simple steatosis through modification of insulin resistance, whereas they act as a progression factor at the advanced stage with fibrosis. Those processes are thought to depend on interaction between NKT cells and CD1d molecule in the liver
Triangular arbitrage as an interaction among foreign exchange rates
We first show that there are in fact triangular arbitrage opportunities in
the spot foreign exchange markets, analyzing the time dependence of the
yen-dollar rate, the dollar-euro rate and the yen-euro rate. Next, we propose a
model of foreign exchange rates with an interaction. The model includes effects
of triangular arbitrage transactions as an interaction among three rates. The
model explains the actual data of the multiple foreign exchange rates well.Comment: 19 pages, 21 eps files embedded. Physica A, to be publishe
Site-dependent Local Spin Susceptibility and Low-energy Excitation in a Weyl Semimetal WTe
Site-dependent local spin susceptibility is investigated with Te
nuclear magnetic resonance in a Weyl semimetal WTe. The nuclear
spin-lattice relaxation rate shows a dependence of the square of
temperature at high temperatures, followed by a constant behavior below 50
K. The temperature dependence features Weyl fermions appearing around the
linearly crossing bands. The Knight shift scales to the square root of
, corroborating a predominant spin contribution in low-lying
excitation. The observed dependence of and on the four Te sites
shows the site-dependent electron correlation and density of states. The
angular profile of the NMR spectrum gives the anisotropic hyperfine coupling
tensor, consistent with hole occupations on Te sites.Comment: 6 pages, 5 figure
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