Asymmetric coalescence of reactively wetting droplets

Coalescence of droplets during reactive wetting is investigated for the liquid Ga/GaAs(001) system. In situmirror electron microscopy reveals that coalescence predominantly involves the motion of one reactive droplet relative to the other. This behaviour differs significantly from coalescence in non-reactive systems and is associated with contact line pinning at a ridge/etch pit edge which is identified using atomic force microscopy and selective etching. A simple geometrical model is presented to describe the pinning

Gutzwiller Projected wavefunctions in the fermonic theory of S=1 spin chains

We study in this paper a series of Gutzwiller Projected wavefunctions for S=1 spin chains obtained from a fermionic mean-field theory for general S>1/2 spin systems [Phys. Rev. B 81, 224417] applied to the bilinear-biquadratic (J-K) model. The free-fermion mean field states before the projection are 1D paring states. By comparing the energies and correlation functions of the projected pairing states with those obtained from known results, we show that the optimized Gutzwiller projected wavefunctions are very good trial ground state wavefunctions for the antiferromagnetic bilinear-biquadratic model in the regime K0). We find that different topological phases of the free-fermion paring states correspond to different spin phases: the weak pairing (topologically non-trivial) state gives rise to the Haldane phase, whereas the strong pairing (topologically trivial) state gives rise to the dimer phase. In particular the mapping between the Haldane phase and Gutwziller wavefunction is exact at the AKLT point K=1/3. The transition point between the two phases determined by the optimized Gutzwiller Projected wavefunction is in good agreement with the known result. The effect of Z2 gauge fluctuations above the mean field theory is analyzed.Comment: 10 pages,7 figure

Asymmetric coalescence of reactively wetting droplets

Coalescence of droplets during reactive wetting is investigated for the liquid Ga/GaAs(001) system. In situmirror electron microscopy reveals that coalescence predominantly involves the motion of one reactive droplet relative to the other. This behaviour differs significantly from coalescence in non-reactive systems and is associated with contact line pinning at a ridge/etch pit edge which is identified using atomic force microscopy and selective etching. A simple geometrical model is presented to describe the pinning

Jet Quenching in the Opposite Direction of a Tagged Photon in High-Energy Heavy-Ion Collisions

We point out that events associated with large $E_T$ direct photons in high-energy heavy-ion collisions can be used to study jet energy loss in dense matter. In such events, the $p_T$ spectrum of charged hadrons from jet fragmentation in the opposite direction of the tagged photon is estimated to be well above the background which can be reliably subtracted at moderately large $p_T$. We demonstrate that comparison between the extracted fragmentation function in $AA$ and $pp$ collisions can be used to determine the jet energy loss and the interaction mean-free-path in the dense matter produced in high-energy heavy-ion collisions.Comment: 4 pages in RevTex twocolumn with embedded psfigure

Ieee access special section editorial: Cloud and big data-based next-generation cognitive radio networks

In cognitive radio networks (CRN), secondary users (SUs) are required to detect the presence of the licensed users, known as primary users (PUs), and to find spectrum holes for opportunistic spectrum access without causing harmful interference to PUs. However, due to complicated data processing, non-real-Time information exchange and limited memory, SUs often suffer from imperfect sensing and unreliable spectrum access. Cloud computing can solve this problem by allowing the data to be stored and processed in a shared environment. Furthermore, the information from a massive number of SUs allows for more comprehensive information exchanges to assist the

The ERA5-Land soil temperature bias in permafrost regions

ERA5-Land (ERA5L) is a reanalysis product derived by running the land component of ERA5 at increased resolution. This study evaluates ERA5L soil temperature in permafrost regions based on observations and published permafrost products. We find that ERA5L overestimates soil temperature in northern Canada and Alaska but underestimates it in mid-low latitudes, leading to an average bias of -0.08 ĝC. The warm bias of ERA5L soil is stronger in winter than in other seasons. As calculated from its soil temperature, ERA5L overestimates active-layer thickness and underestimates near-surface (<1.89

Autofocus for multispectral camera using focus symmetry

Author name used in this publication: Si-Jie ShaoAuthor name used in this publication: John H. Xin2011-2012 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Topologically distinct classes of valence bond solid states with their parent Hamiltonians

We introduce a general method to construct one-dimensional translationally invariant valence bond solid states with a built-in Lie group $G$ and derive their matrix product representations. The general strategies to find their parent Hamiltonians are provided so that the valence bond solid states are their unique ground states. For quantum integer spin-$S$ chains, we discuss two topologically distinct classes of valence bond solid states: One consists of two virtual SU(2) spin-$J$ variables in each site and another is formed by using two $SO(2S+1)$ spinors. Among them, a new spin-1 fermionic valence bond solid state, its parent Hamiltonian, and its properties are discussed in detail. Moreover, two types of valence bond solid states with SO(5) symmetry are further generalized and their respective properties are analyzed as well.Comment: 11 pages, 5 figures; to be published in Physical Review