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In this paper, the general of artificial electromagnetic structure with analog to the natural materials were briefly reviewed. The lattice theory of artificial structure was suggested to be built.
We consider a vibrating triangular mass-truss lattice whose unit cell contains a rigid resonator. The resonators are linked by trusses to the triangular lattice nodal points. We assume that the resonator is tilted, i.e. it is rigidly rotated with respect to the triangular lattice's unit cell by an angle üq. This geometric parameter controls a resonant mode in the spectrum for elastic Bloch waves and...
Strong electric fields are known to create biased adatom migration on metallic surfaces. We present a Kinetic Monte Carlo model that can simulate adatom migration on a tungsten (W) surface in electric fields. We validate our model by using it to calculate the drift velocity of the adatom at different fields and temperature and comparing the results with experimental data from the literature. We obtain...
The discovery of intersubband transitions in III-V semiconductor heterostructures [I] had a huge impact on large parts of the condensed matter physics community and ultimately led to the development of quantum well infrared photodetectors [2] and quantum cascade lasers [3]. One of the main constraints, however, are the strict lattice matching conditions of the heterostructures — limiting the available...
Remarkable advances in cooling and manipulating atomic gases have opened up new avenues to explore fundamental concepts in quantum many-body physics. Synthetically created potentials and control of atom-atom interactions have made it possible to tailor the properties of experimental systems at a microscopic level. This led to the concept of quantum simulation — here a system capable of reproducing...
In the field of topology, it is commonly accepted that for two-dimensional spin-decoupled structures a complete topological characterization is provided by the Chern numbers of the system[1]. The number of the extraordinarily robust chiral edge modes residing in a band gap is given by the sum of the Chern numbers of all bands below this gap. However, this is strictly true only for systems with a Hamiltonian...
Modelling of the field emitter tip and its surface structure at nano and meso-scale is presented. Method for localization of crystallographic faces on the surface is proposed and implemented.
In this work, density functional theory (DFT) computations with van der Waals (vdW) corrections were performed to investigate the dihydrogen bondings and their effects on the electronic and work functions of graphane/silicane bilayer and fully hydrogenated hexagonal boron nitride (fhBN)/silicane bilayer. The type of dihydrogen bonding (C-H···H-Si or N-H···H-Si) greatly affected the stability, electricity...
We introduce composite two-dimensional optical lattices representing a superposition of two mutually rotated square patterns and allowing observation of continuous transformation between aperiodic and completely periodic optical lattices upon variation of the rotation angle θ. A remarkable property of this lattice is that it acquires periodicity only for specific rotation angles cos θ = b/c, sin θ...
Recently, the emergence of topological edge state of matter raises new challenges in understanding the states of condensed matter and phase transitions beyond the the Ginzburg-Landau paradigm. The discovery of topological edge states of condensed matter also stimulate the development in other field, such as the realm of photonics, particularly in photonic crystals (PhCs). In this paper, we systematically...
Topologically nontrivial photonic lattices can reveal topological effects inaccessible in condensed matter systems, and have promising applications including unidirectional light propagation robust against disorder [1]. The first design scalable to optical frequencies employed the Floquet photonic topological insulator concept, in which a time periodic Floquet Hamiltonian was emulated by a helical...
We employ ‘photonic boron nitride’, a silicon photonic crystal slab composed of a honeycomb lattice of holes to observe Dirac physics of guided optical modes. The lattice is composed of two component triangular lattices of different hole-size Δr, which breaks the Dirac cone and opens up an observable band gap.
We study the spatial coherence properties of a system composed of periodic silver nanoparticle arrays covered with fluorescent organic molecule film [1]. The evolution of spatial coherence of the structure is investigated both in weak and strong coupling regimes by systematically varying the coupling strength between the localized molecular excitons and the collective, delocalized modes of the nanoparticle...
Following the measurement of topological invariants in silicon ring resonator systems [1], we report on the progress of investigation of non-classical light transport. In particular, we analyze the transport properties of two-photon wavefunctions in a disorders structure with protected topological edge bands, and examine the robustness of quantum transport properties. Moreover, we discuss a design...
The Axelrod model for the evolution of cultural domains is a stochastic spatial process, with parameters the number of cultural features f and their states q, that has been studied primarily by numerical simulations in social sciences and statistical physics. It may also be viewed as an asynchronous cellular automaton that exhibits a phase transition or, for a certain range of its parameters, as a...
Frequency filtering characteristics by cavities of three different lengths situated in X-shaped photonic crystal waveguide with triangular lattice was simulated by constrained interpolated profile (CIP) method. From analysisi by fast Fourier transform of output signal, the resonant peak frequencies of filtered spectrum by microwave experiment and those by the simulation coincided each other in difference...
We provide a brief discussion on the progress of compatible discretization methods for the simulation of electro-magnetics and multiphysics problems. We revisit some of its success stories and list a few future challenges.
Strontium fluoride (SrF2) is an important member of alkaline-earth fluorides for its intrinsic optical properties and superionic application at animated temperatures as well as thermoluminescent behavior. Using abinitio density functional theory (DFT) method and density functional perturbation theory (DFPT), the structural, phonon frequencies, optical properties and dielectric constants has been investigated...
We monitor the terahertz fingerprints of electronic and structural orders of the charge density wave in 1T-TiSe2 on the femtosecond scale. NIR photoexcitation selectively melts electronic ordering while the structural distortion persists in a coherently excited state.
The tutorial will focus on the remarkable opportunities offered by ultracold quantum gases trapped in optical lattices to address fundamental physics questions ranging from condensed matter physics over statistical physics to high energy physics with table-top experiment.
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