7,739 research outputs found
Boundary Green functions of topological insulators and superconductors
Topological insulators and superconductors are characterized by their gapless
boundary modes. In this paper, we develop a recursive approach to the boundary
Green function which encodes this nontrivial boundary physics. Our approach
describes the various topologically trivial and nontrivial phases as fixed
points of a recursion and provides direct access to the phase diagram, the
localization properties of the edge modes, as well as topological indices. We
illustrate our approach in the context of various familiar models such as the
Su-Schrieffer-Heeger model, the Kitaev chain, and a model for a Chern
insulator. We also show that the method provides an intuitive approach to
understand recently introduced topological phases which exhibit gapless corner
states.Comment: 18 pages, 3 figures (a new Fig. 3 is added), Accepted by Phys. Rev.
Deformation effect on the center-of-mass correction energy in nuclei ranging from Oxygen to Calcium
The microscopic center-of-mass (c.m.) correction energies for nuclei ranging
from Oxygen to Calcium are systematically calculated by both spherical and
axially deformed relativistic mean-field (RMF) models with the effective
interaction PK1. The microscopic c.m. correction energies strongly depend on
the isospin as well as deformation and deviate from the phenomenological ones.
The deformation effect is discussed in detail by comparing the deformed with
the spherical RMF calculation. It is found that the direct and exchange terms
of the c.m. correction energies are strongly correlated with the density
distribution of nuclei and are suppressed in the deformed case.Comment: 7 pages, 3 figures, accepted by Chin.Phys.Let
Deformation effect on the center-of-mass correction energy in nuclei ranging from Oxygen to Calcium
The microscopic center-of-mass (c.m.) correction energies for nuclei ranging
from Oxygen to Calcium are systematically calculated by both spherical and
axially deformed relativistic mean-field (RMF) models with the effective
interaction PK1. The microscopic c.m. correction energies strongly depend on
the isospin as well as deformation and deviate from the phenomenological ones.
The deformation effect is discussed in detail by comparing the deformed with
the spherical RMF calculation. It is found that the direct and exchange terms
of the c.m. correction energies are strongly correlated with the density
distribution of nuclei and are suppressed in the deformed case.Comment: 7 pages, 3 figures, accepted by Chin.Phys.Let
The Operation of the Trade Agreements Program in Overcoming Barriers to Hemisphere Trade
With new technologies, temperature has become a major issue to be considered at system level design. Without taking temperature aspects into consideration, no approach to energy or/and performance optimization will be sufficiently accurate and efficient. In this paper we propose an on-line temperature aware dynamic voltage and frequency scaling (DVFS) technique which is able to exploit both static and dynamic slack. The approach implies an offline temperature aware optimization step and on-line voltage/frequency settings based on temperature sensor readings. Most importantly, the presented approach is aware of the frequency/temperature dependency, by which important additional energy savings are obtained
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