Results for "Xing Lu"

total 13137took 0.13s
High-order Phase Transition in Random HypergrpahsSep 03 2014Aug 02 2018In this paper, we study the high-order phase transition in random $r$-uniform hypergraphs. For a positive integer $n$ and a real $p\in [0,1]$, let $H:=H^r(n,p)$ be the random $r$-uniform hypergraph with vertex set $[n]$, where each $r$-set is selected ... More
High-ordered Random Walks and Generalized Laplacians on HypergraphsFeb 22 2011Despite of the extreme success of the spectral graph theory, there are relatively few papers applying spectral analysis to hypergraphs. Chung first introduced Laplacians for regular hypergraphs and showed some useful applications. Other researchers treated ... More
Loose Laplacian spectra of random hypergraphsSep 15 2011Dec 05 2011Let $H=(V,E)$ be an $r$-uniform hypergraph with the vertex set $V$ and the edge set $E$. For $1\leq s \leq r/2$, we define a weighted graph $G^{(s)}$ on the vertex set ${V\choose s}$ as follows. Every pair of $s$-sets $I$ and $J$ is associated with a ... More
Spectra of edge-independent random graphsApr 27 2012Let $G$ be a random graph on the vertex set $\{1,2,..., n\}$ such that edges in $G$ are determined by independent random indicator variables, while the probability $p_{ij}$ for $\{i,j\}$ being an edge in $G$ is not assumed to be equal. Spectra of the ... More
The Correlation Potential of a Test Ion Near a Strongly Charged PlateNov 01 2013Mar 15 2014We analytically calculate the correlation potential of a test ion near a \emph{strongly} charged plate inside a dilute $m:-n$ electrolyte. We do this by calculating the electrostatic Green's function in the presence of a nonlinear background potential, ... More
Butterfly Velocity Bound and Reverse Isoperimetric InequalityJan 18 2017Jan 24 2017We study the butterfly effect of the AdS planar black holes in the framework of Einstein's general relativity. We find that the butterfly velocities can be expressed by a universal formula $v_{\rm B}^2 = TS/(2V_{\rm th} P)$. In doing so, we come upon ... More
Scalar Hairy Black Holes in General DimensionsDec 18 2013Jan 13 2014We obtain a class of asymptotic flat or (A)dS hairy black holes in D-dimensional Einstein gravity coupled to a scalar with certain scalar potential. For a given mass, the theory admits both the Schwarzschild-Tangherlini and the hairy black holes with ... More
Holographic Complexity and Two Identities of Action GrowthNov 07 2016Nov 23 2016The recently proposed complexity-action conjecture allows one to calculate how fast one can produce a quantum state from a reference state in terms of the on-shell action of the dual AdS black hole at the Wheeler-DeWitt patch. We show that the action ... More
Equivalent classes in matching covered graphsFeb 25 2019Let $G$ be a matching covered graph. Two edges $ e_1$ and $e_2$ of $G$ are {\it equivalent} if $\{e_1,e_2\}\subseteq M$ or $\{e_1,e_2\}\cap M=\emptyset$ for every perfect matching $M$ of $G$. An {\it equivalent class} of $G$ is an edge set $S$ of $G$ ... More
A Fractional Analogue of Brooks' TheoremMar 17 2011Nov 13 2011Let $\Delta(G)$ be the maximum degree of a graph $G$. Brooks' theorem states that the only connected graphs with chromatic number $\chi(G)=\Delta(G)+1$ are complete graphs and odd cycles. We prove a fractional analogue of Brooks' theorem in this paper. ... More
$b$-invariant edges in cubic near-bipartite bricksMay 17 2019May 20 2019A brick is a non-bipartite graph without non-trivial tight cuts. Bricks are building blocks of matching covered graphs. We say that an edge $e$ in a brick $G$ is $b$-invariant if $G-e$ is matching covered and it contains exactly one brick. Kothari, Carvalho, ... More
Improving Deep Pancreas Segmentation in CT and MRI Images via Recurrent Neural Contextual Learning and Direct Loss FunctionJul 16 2017Jul 18 2017Deep neural networks have demonstrated very promising performance on accurate segmentation of challenging organs (e.g., pancreas) in abdominal CT and MRI scans. The current deep learning approaches conduct pancreas segmentation by processing sequences ... More
X-LoRa: An Open Source LPWA NetworkDec 21 2018Jan 26 2019Long Range (LoRa) network is emerging as one of the most promising systems in Low power wide area (LPWA) networks, since it enables the energy-constraint devices distributed over wide areas to establish affordable connectivity. Although the LoRa technology ... More
Efficient Graph Edit Distance Computation and Verification via Anchor-aware Lower Bound EstimationSep 20 2017Oct 01 2017Graph edit distance (GED) is an important similarity measure adopted in a similarity-based analysis between two graphs, and computing GED is a primitive operator in graph database analysis. Partially due to the NP-hardness, the existing techniques for ... More
Bounce Universe and Black Holes from Critical Einsteinian Cubic GravityJul 19 2017We show that there exists a critical point for the coupling constants in Einsteinian cubic gravity where the linearized equations on the maximally-symmetric vacuum vanish identically. We construct an exact isotropic bounce universe in the critical theory ... More
Time Machines and AdS Solitons with Negative MassDec 30 2016We show that in D=2n+1 dimensions, when mass is negative and all angular momenta are non-vanishing, Kerr and Kerr-AdS metrics describe smooth time machines, with no curvature singularity. Turning off the angular momenta appropriately can lead to static ... More
Listwise View Ranking for Image CroppingMay 14 2019Rank-based Learning with deep neural network has been widely used for image cropping. However, the performance of ranking-based methods is often poor and this is mainly due to two reasons: 1) image cropping is a listwise ranking task rather than pairwise ... More
Distributed interaction between computer virus and patch: A modeling studyMay 13 2017The decentralized patch distribution mechanism holds significant promise as an alternative to its centralized counterpart. For the purpose of accurately evaluating the performance of the decentralized patch distribution mechanism and based on the exact ... More
High temperature superconducting phase of HBr under pressure predicted by first-principles calculationsAug 14 2017The high pressure phases of HBr are explored with an ab initio crystal structure search. By taking into account the contribution of zero-point energy (ZPE), we find that the P4/nmm phase of HBr is thermodynamically stable in the pressure range from 150 ... More
Charge Renormalization and Charge Oscillation in Asymmetric Primitive ModelFeb 24 2015Feb 19 2016The Debye charging method is generalized to study the linear response properties of the asymmetric primitive model for electrolytes. Analytic results are obtained for the effective charge distributions of constituent ions inside the electrolyte, from ... More
Phenomenological Theory of Isotropic-Genesis Nematic ElastomersMar 05 2012We consider the impact of the elastomer network on the structure and fluctuations in the isotropic-genesis nematic elastomer, via a phenomenological model that underscores the role of network compliance. The model contains a network-mediated nonlocal ... More
Polydomain structure and its origins in isotropic-genesis nematic elastomersJan 06 2011We address the physics of nematic liquid crystalline elastomers randomly crosslinked in the isotropic state. To do this, we construct a phenomenological effective replica Hamiltonian in terms of two order-parameter fields: one for the vulcanization, the ... More
Godel Universe from String TheoryDec 06 2016Dec 12 2016G\"odel universe is a direct product of a line and a three-dimensional spacetime we call G$_\alpha$. In this paper, we show that the G\"odel metrics can arise as exact solutions in Einstein-Maxwell-Axion, Einstein-Proca-Axion, or Freedman-Schwarz gauged ... More
Pancreas Segmentation in CT and MRI Images via Domain Specific Network Designing and Recurrent Neural Contextual LearningMar 30 2018Automatic pancreas segmentation in radiology images, eg., computed tomography (CT) and magnetic resonance imaging (MRI), is frequently required by computer-aided screening, diagnosis, and quantitative assessment. Yet pancreas is a challenging abdominal ... More
Topological thermal Hall effect driven by fluctuation of spin chirality in frustrated antiferromagnetsNov 18 2018Nov 22 2018By revealing an underlying relation between the Dzyaloshinskii-Moriya interaction (DMI) and the scalar spin chirality, we develop the theory of magnon thermal Hall effects in antiferromagnetic systems. The dynamic fluctuation of the scalar chirality is ... More
Anisotropic deformation of Rydberg blockade sphere in few-atom systemsSep 02 2013Rydberg blockade sphere persists an intriguing picture by which a number of collective many-body effects caused by the strong Rydberg-Rydberg interactions can be clearly understood and profoundly investigated. In the present work, we develop a new definition ... More
Initial Fragmentation in the Infrared Dark Cloud G28.53-0.25Mar 30 2015To study the fragmentation and gravitational collapse of dense cores in infrared dark clouds (IRDCs), we have obtained submillimeter continuum and spectral line data as well as multiple inversion transitions of NH3 and H2O maser data of four massive clumps ... More
Multifractal characteristics and return predictability in the Chinese stock marketsJun 20 2018By adopting Multifractal detrended fluctuation (MF-DFA) analysis methods, the multifractal nature is revealed in the high-frequency data of two typical indexes, the Shanghai Stock Exchange Composite 180 Index (SH180) and the Shenzhen Stock Exchange Composite ... More
Horndeski Gravity and the Violation of Reverse Isoperimetric InequalityMay 24 2017Jun 04 2017We consider Einstein-Horndeski-Maxwell gravity, together with a cosmological constant and multiple Horndeski axions. We construct charged AdS planar black holes in general dimensions where the Horndeski anxions span over the planar directions. We analyse ... More
The Fractional Chromatic Number of Triangle-free Graphs with $Δ\leq 3$Nov 10 2010Jul 25 2012Let $G$ be any triangle-free graph with maximum degree $\Delta\leq 3$. Staton proved that the independence number of $G$ is at least 5/14n. Heckman and Thomas conjectured that Staton's result can be strengthened into a bound on the fractional chromatic ... More
Monochromatic 4-term arithmetic progressions in 2-colorings of $\mathbb Z_n$Jul 14 2011This paper is motivated by a recent result of Wolf \cite{wolf} on the minimum number of monochromatic 4-term arithmetic progressions(4-APs, for short) in $\Z_p$, where $p$ is a prime number. Wolf proved that there is a 2-coloring of $\Z_p$ with 0.000386% ... More
Dynamically generated $J^P=1/2^-(3/2^-)$ singly charmed and bottom heavy baryonsSep 10 2014Jul 26 2015Approximate heavy-quark spin and flavor symmetry and chiral symmetry play an important role in our understanding of the nonperturbative regime of strong interactions. In this work, utilizing the unitarized chiral perturbation theory, we explore the consequences ... More
A cost-effective rumor-containing strategySep 08 2017Dec 28 2017This paper addresses the issue of suppressing a rumor using the truth in a cost-effective way. First, an individual-level dynamical model capturing the rumor-truth mixed spreading processes is proposed. On this basis, the cost-effective rumor-containing ... More
Maximizing the overall profit of a word-of-mouth marketing campaign: A modeling studyApr 23 2017As compared to the traditional advertising, the word-of-mouth (WOM) communications have striking advantages such as significantly lower cost and rapid delivery; this is especially the case with the popularity of online social networks. This paper addresses ... More
Defend against advanced persistent threats: An optimal control approachSep 09 2017Dec 28 2017The new cyber attack pattern of advanced persistent threat (APT) has posed a serious threat to modern society. This paper addresses the APT defense problem, i.e., the problem of how to effectively defend against an APT campaign. Based on a novel APT attack-defense ... More
Predictive Deployment of UAV Base Stations in Wireless Networks: Machine Learning Meets Contract TheoryNov 03 2018In this paper, a novel framework that enables a predictive deployment of unmanned aerial vehicles (UAVs) as flying base stations (BSs) to complement ground cellular systems in face of steep surges in wireless traffic is proposed. Considering downlink ... More
High-order Phase Transition in Random HypergrpahsSep 03 2014In this paper, we study the high-order phase transition in random $r$-uniform hypergraphs. For a positive integer $n$ and a real $p\in [0,1]$, let $H:=H^r(n,p)$ be the random $r$-uniform hypergraph on the vertex set $[n]$, where each $r$-set is an edge ... More
Simulating Z_2 topological insulators via a one-dimensional cavity optomechanical cells arrayNov 15 2018We propose a novel scheme to simulate Z_2 topological insulators via one-dimensional (1D) cavity optomechanical cells array. The direct mapping between 1D cavity optomechanical cells array and 2D quantum spin Hall (QSH) system can be achieved by using ... More
High-pressure phases of Weyl semimetals NbP, NbAs, TaP and TaAsAug 14 2017The high pressure phase diagrams of TaAs family (NbP, NbAs, TaP and TaAs) are explored systematically using crystal structure search together with first-principles calculations. Our calculations show that NbAs and TaAs have similar phase diagrams and ... More
PTrix: Efficient Hardware-Assisted Fuzzing for COTS BinaryMay 25 2019Despite its effectiveness in uncovering software defects, American Fuzzy Lop (AFL), one of the best grey-box fuzzers, is inefficient when fuzz-testing source-unavailable programs. AFL's binary-only fuzzing mode, QEMU-AFL, is typically 2-5X slower than ... More
Cavity-induced switching between localized and extended states in a non-interacting Bose-Einstein condensateAug 24 2011Oct 08 2011We study an ultracold atom-cavity coupling system, which had been implemented in experiment to display weak light nonlinearity [S. Gupta \textit{et al}., Phys. Rev. Lett. \textbf{99}, 213601 (2007)]. The model is described by a non-interacting Bose-Einstein ... More
Testing Technicolor Models in Top Quark Pair Production at High Energy Photon CollidersJul 27 1997Nov 29 1997We study pseudo-Goldstone boson corrections to top quark pair production rates in technicolor models with and without topcolor at the E=0.5 teV and 1.5 TeV photon colliders. We find that, for reasonable ranges of the parameters, the corrections are large ... More
Quasinormal modes of Dirac field perturbation in Reissner-Nordström black hole surrounded by quintessenceOct 27 2009Oct 30 2009The dirac quasinormal modes of the Reissner-Nordstr\"om black hole surrounded by quintessence are investigated using the third WKB approximation. We find that the magnitude of the imaginary part of the quasinormal mode frequencies increases firstly and ... More
Nonsymmorphic symmetry protected node-line semimetal in the trigonal YH3Dec 29 2017Using ab initio calculations based on density-functional theory and effective model analysis, we propose that the trigonal YH3(Space Group: P-3c1) at ambient pressure is a node-line semimetal when spin-orbit coupling (SOC) is ignored. This trigonal YH3 ... More
Cosmological Time Crystals From Einstein-Cubic GravitiesJul 04 2018By including appropriate Riemman cubic invariants, we find that the dynamics of classical time crystals can be straightforwardly realized in Einstein gravity on the FLRW metric. The time reflection symmetry is spontaneously broken in the two vacua with ... More
Assessing the risk of advanced persistent threatsJul 08 2017Dec 28 2017As a new type of cyber attacks, advanced persistent threats (APTs) pose a severe threat to modern society. This paper focuses on the assessment of the risk of APTs. Based on a dynamic model characterizing the time evolution of the state of an organization, ... More
Analysis of the effectiveness of the truth-spreading strategy for inhibiting rumorsMay 17 2017Spreading truths is recognized as a feasible strategy for inhibiting rumors. This paper is devoted to assessing the effectiveness of the truth-spreading strategy. An individual-level rumor-truth spreading model (the generic URTU model) is derived. Under ... More
A discount strategy in word-of-mouth marketing and its assessmentApr 23 2017This paper addresses the discount pricing in word-of-mouth (WOM) marketing. A new discount strategy known as the Infection-Based Discount (IBD) strategy is proposed. The basic idea of the IBD strategy lies in that each customer enjoys a discount that ... More
On Compression of Unsupervised Neural Nets by Pruning Weak ConnectionsJan 21 2019Jan 23 2019Unsupervised neural nets such as Restricted Boltzmann Machines(RBMs) and Deep Belif Networks(DBNs), are powerful in automatic feature extraction,unsupervised weight initialization and density estimation. In this paper,we demonstrate that the parameters ... More
Cooperative three- and four- player quantum gamesAug 12 2002A cooperative multi-player quantum game played by 3 and 4 players has been studied. Quantum superposed operator is introduced in this work which solves the non-zero sum difficulty in previous treatment. The role of quantum entanglement of the initial ... More
The large unsaturated magnetoresistance of Weyl semimetalsSep 14 2015Sep 15 2015The Weyl semimetal (WSM) is a novel topological gapless state with promises exotic transport due to chiral anomaly. Recently, a family of nonmagnetic WSM candidates including TaAs, NbAs, NbP etc is confirmed by first principle calculation and experiments. ... More
Neural Machine Translation Advised by Statistical Machine TranslationOct 17 2016Dec 30 2016Neural Machine Translation (NMT) is a new approach to machine translation that has made great progress in recent years. However, recent studies show that NMT generally produces fluent but inadequate translations (Tu et al. 2016b; Tu et al. 2016a; He et ... More
Single Magnetic Impurity in Tilted Dirac Surface StatesNov 02 2017Dec 29 2017We utilize variational method to investigate the Kondo screening of a spin-1/2 magnetic impurity in tilted Dirac surface states with the Dirac cone tilted along the $k_y$-axis. We mainly study about the effect of the tilting term on the binding energy ... More
VLA observations of ammonia in high-mass star formation regionsMay 30 2014We report systematic mapping observations of the NH$_{3}$ (1,1) and (2,2) inversion lines towards 62 high-mass star-forming regions using VLA in its D and DnC array configurations. The VLA images cover a spatial dynamic range from 40$"$ to 3$"$, allowing ... More
Security evaluation of cyber networks under advanced persistent threatsJul 12 2017This paper is devoted to measuring the security of cyber networks under advanced persistent threats (APTs). First, an APT-based cyber attack-defense process is modeled as an individual-level dynamical system. Second, the dynamic model is shown to exhibit ... More
An Open Source Modeling Framework for Interdependent Energy-Transportation- Communication Infrastructure in Smart and Connected CommunitiesApr 07 2019Infrastructure in future smart and connected communities is envisioned as an aggregate of public services, including the energy, transportation and communication systems, all intertwined with each other. The intrinsic interdependency among these systems ... More
The damage inflicted by a computer virus: A new estimation methodJun 07 2017This paper addressed the issue of estimating the damage caused by a computer virus. First, an individual-level delayed SIR model capturing the spreading process of a digital virus is derived. Second, the damage inflicted by the virus is modeled as the ... More
On the effectiveness of the truth-spreading/rumor-blocking strategy for restraining rumorsMay 28 2017Spreading truths and blocking rumors are two typical strategies for inhibiting rumors. In practice, a tradeoff between the two strategies, which is known as the TSRB strategy, may achieve a better cost-effectiveness. This paper is devoted to assessing ... More
The Galactic Center Molecular Cloud Survey. I. A Steep Linewidth-Size Relation & Suppression of Star FormationOct 11 2016The Central Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way is a star formation (SF) environment with very extreme physical properties. Exploration of SF in this region is important because (i) this region allows us to test models of ... More
Higher-Derivative Gravity with Non-minimally Coupled Maxwell FieldDec 30 2015We construct higher-derivative gravities with a non-minimally coupled Maxwell field. The Lagrangian consists of polynomial invariants built from the Riemann tensor and the Maxwell field strength in such a way that the equations of motion are second order ... More
A Massive Prestellar Clump Hosting no High-Mass CoresApr 26 2017The Infrared Dark Cloud (IRDC) G028.23-00.19 hosts a massive (1,500 Msun), cold (12 K), and 3.6-70 um IR dark clump (MM1) that has the potential to form high-mass stars. We observed this prestellar clump candidate with the SMA (~3.5" resolution) and JVLA ... More
The Galactic Center Molecular Cloud Survey. I. A Steep Linewidth-Size Relation & Suppression of Star FormationOct 11 2016Nov 04 2016The Central Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way is a star formation (SF) environment with very extreme physical properties. Exploration of SF in this region is important because (i) this region allows us to test models of ... More
The $Λ_c(2595)$ resonance as a dynamically generated state: the compositeness condition and the large $N_c$ evolutionMar 17 2016Recent studies have shown that the well established $\Lambda_c(2595)$ resonance contains a large meson-baryon component, which can vary depending on the specific formalism. In this work, we examine such a picture by utilizing the compositeness condition ... More
Observation of eight-photon entanglementMay 31 2011Using ultra-bright sources of pure-state entangled photons from parametric down conversion, an eight-photon interferometer and post-selection detection, we demonstrate the ability to experimentally manipulate eight individual photons and report the creation ... More
Experimental measurement-based quantum computing beyond the cluster-state modelApr 23 2010Jun 14 2012The paradigm of measurement-based quantum computation opens new experimental avenues to realize a quantum computer and deepens our understanding of quantum physics. Measurement-based quantum computation starts from a highly entangled universal resource ... More
Deeply Embedded Protostellar Population in the 20 km s-1 Cloud of the Central Molecular ZoneOct 16 2015We report the discovery of a population of deeply embedded protostellar candidates in the 20 km s$^{-1}$ cloud, one of the massive molecular clouds in the Central Molecular Zone (CMZ) of the Milky Way, using interferometric submillimeter continuum and ... More
SMA Observations of Extended $\rm{CO}\,(J=2-1)$ Emission in Interacting Galaxy NGC 3627Aug 22 2018We present moderate (${\sim}5^{\prime\prime}$) and high angular resolution (${\sim}1^{\prime\prime}$) observations of $^{12}\rm{CO\,}(J=2-1)$ emission toward nearby, interacting galaxy NGC 3627 taken with the Submillimeter Array (SMA). These SMA mosaic ... More
Direct experimental verification of quantum commutation relations for Pauli operatorsFeb 08 2010We propose and demonstrate scheme for direct experimental testing of quantum commutation relations for Pauli operators. The implemented device is an advanced quantum processor that involves two programmable quantum gates. Depending on a state of two-qubit ... More
Synthesis, characterization and physical properties of layered bismuthide PtBi$_2$May 29 2016Jun 02 2016We report details of single crystal growth of stoichiometric bismuthide PtBi$_2$ whose structure consists of alternate stacking of Pt layer sandwiched by Bi bilayer along the $c$-axis. The compound crystallizes in space group P-3 with a hexagonal unit ... More
Spontaneous PT symmetry breaking in non-Hermitian coupled cavities arrayNov 14 2018We study the effects of the position of the passive and active cavities on the spontaneous parity-time (PT) symmetry breaking behavior in non-Hermitian coupled cavities array model. We analyze and discuss the energy eigenvalue spectrums and PT symmetry ... More
SMA Observations of the Hot Molecular Core IRAS 18566+0408Aug 24 2017We present Submillimeter Array (SMA) observations toward the high-mass star-forming region IRAS 18566+0408. Observations at 1.3 mm continuum and in several molecular line transitions were performed in the compact (2."4 angular resolution) and very-extended ... More
The Galactic Center Molecular Cloud Survey. II. A Lack of Dense Gas & Cloud Evolution along Galactic Center OrbitsOct 11 2016Jun 08 2017We present the first systematic study of the density structure of clouds found in a complete sample covering all major molecular clouds in the Central Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way. This is made possible by using data ... More
Implementation of a Measurement-Device-Independent Entanglement WitnessApr 16 2014Entanglement, the essential resource in quantum information processing, should be witnessed in many tasks such as quantum computing and quantum communication. The conventional entanglement witness method, relying on an idealized implementation of measurements, ... More
Spatial anisotropy of Kondo screening cloud in a type-II Weyl semimetalApr 10 2019We theoretically study the Kondo screening of a spin-1/2 magnetic impurity in the bulk of a type-II Weyl semimetal (WSM) by use of the variational wave function method. We consider a type-II WSM model with two Weyl nodes located on the $k_z$-axis, and ... More
Complexity and Two Identities of Action GrowthNov 07 2016The recently proposed complexity-action conjecture allows one to calculate how fast one can produce a quantum state from a reference state in terms of the on-shell action of the dual AdS black hole at the Wheeler-DeWitt patch. We show that the action ... More
Cooperative Multi-Agent Policy Gradients with Sub-optimal DemonstrationDec 05 2018Many reality tasks such as robot coordination can be naturally modelled as multi-agent cooperative system where the rewards are sparse. This paper focuses on learning decentralized policies for such tasks using sub-optimal demonstration. To learn the ... More
Charged Plate in Asymmetric Electrolytes: One-loop Renormalization of Surface Charge Density and Debye Length due to Ionic CorrelationsFeb 12 2016The self-consistent field theory (SCFT) is used to study the mean potential near a charged plate inside a $m:-n$ electrolyte. A perturbation series is developed in terms of $g = 4 \pi b/\ell_{\rm {\scriptscriptstyle DB}}$, where $b, \ell_{\rm{\scriptscriptstyle ... More
Pressure-induced metallization and superconducting phase in ReS2Feb 14 2017Among the family of TMDs, ReS2 takes a special position, which crystalizes in a unique distorted low-symmetry structure at ambient conditions. The interlayer interaction in ReS2 is rather weak, thus its bulk properties are similar to that of monolayer. ... More
Survey of Cognitive Radio Techniques in Wireless NetworkApr 29 2011In this report, I surveyed the cognitive radio technique in wireless networks. Researched several kinds of cognitive techniques about their advantages and disadvantages.
Gap Anisotropy in Iron-Based Superconductors: A Point-Contact Andreev Reflection Study of BaFe$_{2-x}$Ni$_{x}$As$_2$ Single CrystalsJun 15 2011Nov 11 2011We report a systematic investigation on c-axis point-contact Andreev reflection (PCAR) in BaFe$_{2-x}$Ni$_x$As$_2$ superconducting single crystals from underdoped to overdoped regions (0.075 $\leq x\leq 0.15$). At optimal doping ($x=0.1$) the PCAR spectrum ... More
Band-selective shaped pulse for high fidelity quantum control in diamondApr 09 2014Apr 10 2014High fidelity quantum control over qubits is of crucial importance for realistic quantum computing, and it turns to be more challenging when there are inevitable interactions among qubits. By employing a bandselective shaped pulse, we demonstrate a high ... More
Origin of the superconductivity of WTe2 under pressureDec 02 2015Apr 13 2016Tungsten ditelluride (WTe2) has attracted significant attention due to its interesting electronic properties, such as the unsaturated magnetoresistance and superconductivity. Recently, it has been proposed to be a new type of Weyl semimetal, which is ... More
A Systematic Study on Energy Dependence of Quasi-Periodic Oscillation Frequency in GRS 1915+105Jul 19 2011Aug 01 2011Systematically studying all the RXTE/PCA observations for GRS 1915+105 before November 2010, we have discovered three additional patterns in the relation between Quasi-Periodic Oscillation (QPO) frequency and photon energy, extending earlier outcomes ... More
Anisotropic Fermi Surface and Quantum Limit Transport in High Mobility 3D Dirac Semimetal Cd3As2Dec 01 2014Dec 17 2014The three-dimensional (3D) topological Dirac semimetal is a new topological phase of matter, viewed as the 3D analogy of graphene with a linear dispersion in the 3D momentum space. Here, we report the angular dependent magnetotransport in Cd3As2 single ... More
Local and collective magnetism of EuFe$_2$As$_2$Mar 28 2017We present an experimental study of the local and collective magnetism of $\mathrm{EuFe_2As_2}$, that is isostructural with the high temperature superconductor parent compound $\mathrm{BaFe_2As_2}$. In contrast to $\mathrm{BaFe_2As_2}$, where only Fe ... More
Experimental Test of Bell inequalities with Six-Qubit Graph StatesJun 18 2009Jan 04 2011We report on the experimental realization of two different Bell inequality tests based on six-qubit linear-type and Y-shape graph states. For each of these states, the Bell inequalities tested are optimal in the sense that they provide the maximum violation ... More
Experimental Realization of a Controlled-NOT Gate with Four-Photon Six-Qubit Cluster StatesMay 13 2009Mar 30 2010We experimentally demonstrate an optical controlled-NOT (CNOT) gate with arbitrary single inputs based on a 4-photon 6-qubit cluster state entangled both in polarization and spatial modes. We first generate the 6-qubit state, and then by performing single-qubit ... More
Experimental demonstration of a hyper-entangled ten-qubit Schrödinger cat stateSep 24 2008Coherent manipulation of an increasing number of qubits for the generation of entangled states has been an important goal and benchmark in the emerging field of quantum information science. The multiparticle entangled states serve as physical resources ... More
Star Formation Rates of Massive Molecular Clouds in the Central Molecular ZoneJan 23 2019Feb 21 2019We investigate star formation at very early evolutionary phases in five massive clouds in the inner 500 pc of the Galaxy, the Central Molecular Zone. Using interferometer observations of H$_2$O masers and ultra-compact H II regions, we find evidence of ... More
Filamentary Fragmentation and Accretion in High-Mass Star-Forming Molecular CloudsJan 18 2018Filamentary structures are ubiquitous in high-mass star-forming molecular clouds. Their relation with high-mass star formation is still to be understood. Here we report interferometric observations toward 8 filamentary high-mass star-forming clouds. A ... More
A new topological semimetal with iso-energetic Weyl fermions in TaAs under high pressureSep 24 2015Nov 11 2015TaAs as one of the experimentally discovered topological Weyl semimetal has attracted intense interests recently. The ambient TaAs has two types of Weyl nodes which are not on the same energy level. As an effective way to tune lattice parameters and electronic ... More
$b$-invariant edges in cubic near-bipartite brickMay 17 2019A brick is a non-bipartite graph without non-trivial tight cuts. Bricks are building blocks of matching covered graphs. We say that an edge $e$ in a brick $G$ is $b$-invariant if $G-e$ is matching covered and it contains exactly one brick. Kothari, Carvalho, ... More
Extraordinarily bound quasi-one-dimensional trions in two-dimensional phosphorene atomic semiconductorsNov 22 2014The anisotropic nature of the new two-dimensional (2D) material phosphorene, in contrast to other 2D materials such as graphene and transition metal dichalcogenide (TMD) semiconductors, allows excitons to be confined in a quasi-one-dimensional (1D) space ... More
Recovery of Saturated $γ$ Signal Waveforms by Artificial Neural NetworksOct 18 2018Particle may sometimes have energy outside the range of radiation detection hardware so that the signal is saturated and useful information is lost. We have therefore investigated the possibility of using an Artificial Neural Network (ANN) to restore ... More
Oscillating planar Hall response from the surface electrons in bulk crystal Sn doped Bi1.1Sb0.9Te2SApr 12 2018We report the low-temperature magneto-transport in the bulk-insulating single crystal of topological insulator Sn doped Bi1.1Sb0.9Te2S. The Shubnikov-de Haas oscillations appear with their reciprocal frequency proportional to cos/theta , demonstrating ... More
Palladium Diselenide Long-Wavelength Infrared Photodetector with High Sensitivity and StabilityFeb 06 2019A long-wavelength infrared (IR) photodetector based on two-dimensional materials working at room temperature would have wide applications in many aspects in remote sensing, thermal imaging, biomedical optics, and medical imaging. However, sub-bandgap ... More
Quantifying the complex permittivity and permeability of magnetic nanoparticlesApr 06 2015The complex permittivity and permeability of superparamagnetic iron-oxide nanoparticles has been quantified using a circular waveguide assembly with a static magnetic field to align the nanoparticle's magnetization. The high sensitivity of the measurement ... More
On-Demand Single Photons with High Extraction Efficiency and Near-Unity Indistinguishability from a Resonantly Driven Quantum Dot in a MicropillarJan 03 2016May 13 2016Scalable photonic quantum technologies require on-demand single-photon sources with simultaneously high levels of purity, indistinguishability, and efficiency. These key features, however, have only been demonstrated separately in previous experiments. ... More
Restrictions of eigenfunctions to totally geodesic submanifolds of codimension 2Jun 30 2016In this paper, we measure the maximum concentration of eigenfunctions restricted to totally geodesic submanifolds of codimension 2. N. Burq, P. G\'erard, and N. Tzvetkov obtained $L^p$ estimates for eigenfunctions restricted to submanifolds. Their results ... More
On the decomposition of random hypergraphsOct 16 2015Nov 08 2015For an $r$-uniform hypergraph $H$, let $f(H)$ be the minimum number of complete $r$-partite $r$-uniform subhypergraphs of $H$ whose edge sets partition the edge set of $H$. For a graph $G$, $f(G)$ is the bipartition number of $G$ which was introduced ... More