420 research outputs found

    Effects of Long-Range Interactions on Magnetic Excitations and Phase Transition on a Magnetically Frustrated Square Lattice

    Full text link
    We investigate the effects of long-range interaction on the magnetic excitations and the competition between magnetic phases on a frustrated square lattice. Applying the spin wave theory and assisted with symmetry analysis, we obtain analytical expression for spin wave spectrum of competing Neel and (pi, 0) stripe states of systems containing any-order long-range interactions. In the specific case of long-range interactions with power-law decay, we found surprisingly that staggered long-range interaction suppresses quantum fluctuation and enlarges the ordered moment, especially in the Neel state, and thus extends its phase boundary to the stripe state. Our findings only illustrate the rich possibilities of the roles of long-range interactions, and advocate future investigations in other magnetic systems with different structures of interactions.Comment: 9 pages, 9 figure

    Cross-cultural adaptation of Chinese international students in Europe

    Get PDF
    Chinese students have increasingly chosen European countries as destinations for oversea education. Cross-cultural adaptation is a great challenge for Chinese international students in their oversea education endeavors in Europe. The study aims to understand cross-cultural adaptation challenge of Chinese students studying in Europe, and analyzes the main factors affecting their cross-cultural adaptation. Specifically, this study investigated the cross-cultural adaptation of Chinese international students in Europe on three dimensions of daily life, academic and communication. This study was conducted by semi-structured interviews of 20 Chinese students with studying experience in Europe. The study found the following results. Most respondents in this study have a high degree of cross-cultural adaptation. The respondents have higher socio-cultural adaptation than psychological adaptation in daily life and academics, but lower social-cultural adaptation than psychological adaptation in communication. Among the influencing factors, the purpose and expectation of coming to Europe have a significant impact on the cross-cultural adaptation of international students; economic factors are an important variable affecting cross-cultural adaptation of international students.Os estudantes chineses escolhem cada vez mais os países europeus como destino para os seus estudos no estrangeiro. A adaptação intercultural é um grande desafio para os estudantes chineses internacionais que estudam na Europa. Esta pesquisa teve como objetivo compreender os desafios da adaptação intercultural de estudantes chineses na Europa e analisar os principais fatores que influenciam a adaptação intercultural. Especificamente, a pesquisa analisou a adaptação intercultural de estudantes chineses na Europa, nas dimensões da vida cotidiana, acadêmica e comunicacional. Foram realizadas entrevistas semiestruturadas com 20 estudantes chineses com experiência de estudo na Europa. O estudo encontrou os seguintes resultados. Neste estudo, a maioria dos entrevistados apresentou um alto grau de adaptação transcultural. A adaptação psicológica na vida cotidiana e na academia fica atrás dos efeitos da adaptação sociocultural, interação social e adaptação psicológica e sociocultural. O estudo encontrou os seguintes resultados. Neste estudo, a maioria dos entrevistados apresentou alto grau de adaptação transcultural. A adaptação sociocultural dos entrevistados foi superior à adaptação psicológica na vida cotidiana e acadêmica, enquanto a adaptação sociocultural foi inferior à adaptação psicológica na comunicação. Entre os fatores de influência, o propósito e as expectativas de vir para a china tiveram um impacto significativo na adaptação intercultural dos estudantes estrangeiros; Fatores econômicos são importantes variáveis que influenciam a adaptação transcultural de estudantes estrangeiros

    Return and Volatility Spillovers across Equity Markets in Mainland China, Hong Kong and the United States

    Get PDF
    Abstract: Examinations of the dynamics of daily returns and volatility in stock markets of the U.S., Hong Kong and mainland China (Shanghai and Shenzhen) over 2 January 2001 to 8 February 2013 suggest: (1) evidence of unidirectional return spillovers from the U.S. to the other three markets; but no spillover between Hong Kong and either of the two mainland China markets; (2) evidence of unidirectional ARCH and GARCH effects from the U.S. to the other three markets; (3) correlations of returns vary across markets, with the highest correlation of 93.5% between the two Chinese markets, medium correlation of 30% between mainland China and Hong Kong markets and low correlations of 6.4% and 7.2% between the U.S. and China's two markets; thus, international investors may benefit by allocating their assets in China's markets; (4) the patterns of dynamic conditional correlations from the DCC model suggest an increase in correlation between China and other stock markets since the most recent financial crisis of 2007

    van der Waals Bonded Co/h-BN Contacts to Ultrathin Black Phosphorus Devices

    Full text link
    Due to the chemical inertness of 2D hexagonal-Boron Nitride (h-BN), few atomic-layer h-BN is often used to encapsulate air-sensitive 2D crystals such as Black Phosphorus (BP). However, the effects of h-BN on Schottky barrier height, doping and contact resistance are not well known. Here, we investigate these effects by fabricating h-BN encapsulated BP transistors with cobalt (Co) contacts. In sharp contrast to directly Co contacted p-type BP devices, we observe strong n-type conduction upon insertion of the h-BN at the Co/BP interface. First principles calculations show that this difference arises from the much larger interface dipole at the Co/h-BN interface compared to the Co/BP interface, which reduces the work function of the Co/h-BN contact. The Co/h-BN contacts exhibit low contact resistances (~ 4.5 k-ohm), and are Schottky barrier free. This allows us to probe high electron mobilities (4,200 cm2/Vs) and observe insulator-metal transitions even under two-terminal measurement geometry

    Unraveling the Impact of Visual Cues in Online Portraits on Workers’ Employability in Digital Labor Markets

    Get PDF
    Online portraits constitute a pervasive and critical signal in digital labor markets in that workers can boost their employability by manipulating select visual cues embedded in these portraits. Consequently, we attempt to unravel how visual cues embedded in workers’ portraits within digital labor markets can collectively influence constituent dimensions of employability. Notably, we advance a non-verbal cues classification model that differentiates among demographic, physical appearance, image quality, and non-verbal behavioral cues as focal determinants affecting one’s employment status, the number of job offers received, and rehiring probability. Employing computer vision and deep learning algorithmic techniques to analyze the online portraits and personal information of 53,950 workers on Upwork.com, we demonstrate that visual cues embedded in profile portraits exert a significant effect on workers’ employability in digital labor markets
    corecore