Mapping Child Well-Being in Duval County, FL

Analyzes the distribution of neighborhood, education, and health/environmental opportunity; impact on health and education outcomes; demographics of those in Children's Commission programs; and marginalized neighborhoods' conditions. Outlines strategies

Theory of electron-phonon interaction in a nonequilibrium open electronic system

We study the effects of time-independent nonequilibrium drive on an open 2D electron gas system coupled to 2D longitudinal acoustic phonons using the Keldysh path integral method. The layer electron-phonon system is defined at the two-dimensional interface between a pair of three-dimensional Fermi liquid leads, which act both as a particle pump and an infinite bath. The nonequilibrium steady state is achieved in the layer by assuming the leads to be thermally equilibrated at two different chemical potentials. This subjects the layer to an out-of-plane voltage $V$ and drives a steady-state charge current perpendicular to the system. We compute the effects of small voltages (V\ll\w_D) on the in-plane electron-phonon scattering rate and the electron effective mass at zero temperature. We also find that the obtained onequilibrium modification to the acoustic phonon velocity and the Thomas-Fermi screening length reveal the possibility of tuning these quantities with the external voltage.Comment: 14 pages, 4 figure

Nonlocal Dispersion Cancellation using Entangled Photons

A pair of optical pulses traveling through two dispersive media will become broadened and, as a result, the degree of coincidence between the optical pulses will be reduced. For a pair of entangled photons, however, nonlocal dispersion cancellation in which the dispersion experienced by one photon cancels the dispersion experienced by the other photon is possible. In this paper, we report an experimental demonstration of nonlocal dispersion cancellation using entangled photons. The degree of two-photon coincidence is shown to increase beyond the limit attainable without entanglement. Our results have important applications in fiber-based quantum communication and quantum metrology.Comment: 8 pages, 5 figure

A Guide to Navigating Existing and Emerging Sources of Local VMT and Travel Data

As the crisis of climate change looms, transportation policy in California continues to emphasize sustainability in land-use and transportation decisions. This report evaluates the implementation of two sustainability-focused policies (Senate Bill 375 and 743) by local governments and the current-state-of-the-practices by metropolitan planning organizations (MPOs) in assisting them in California. The research focuses on local governments’ access and use of vehicle miles traveled (VMT) and transportation data for achieving VMT and greenhouse gas (GHG) reduction by land-use planning. The research also examines the role of MPOs in providing needed transportation data, training, and technical support to its local members to help them quantify VMT impacts of land-use plans and projects. Through surveys and interviews of 539 city and county governments and 18 MPOs in California, the research team analyzes current practices. Findings include that local governments utilize automobile data more frequently than alternative modes, and do not heavily rely on MPOs for obtaining transportation data. Local governments recognized the need for more transportation data and were particularly interested in publicly available sources. The MPOs reported that VMT/annual average daily traffic data and origin-destination matrix were most frequently requested. More sophisticated data such as travel-time matrix and mode-share scheme were considered useful by the MPOs, while requests were very low. Based on the results of the conducted surveys, interviews, and our analyses, we developed a transportation data guide for local governments that could help them access data for achieving VMT/GHG emission reduction via land-use planning. The guide has two parts, one for general plan update and any land-use plans along with SB 375 and the other for VMT analysis for project-level California Environmental Quality Act reviews. The guide includes several different approaches that can be chosen and tried by local governments depending on their resource level and geographic, social, and physical characteristics. These findings can facilitate the access and use of transportation data to aid in sustainable land-use planning for the betterment of local communities and the planet

Nonequilibrium quantum criticality in bilayer itinerant ferromagnets

We present a theory of nonequilibrium quantum criticality in a coupled bilayer system of itinerant electron magnets. The model studied consists of the first layer subjected to an inplane current and open to an external substrate. The second layer is closed and subject to no direct external drive, but couples to the first layer via short-ranged spin exchange interaction. No particle exchange is assumed between the layers. Starting from a microscopic fermionic model, we derive an effective action in terms of two coupled bosonic fields which are related to the magnetization fluctuations of the two layers. When there is no interlayer coupling, the two bosonic modes possess different dynamical critical exponents z with z=2 (z=3) for the first (second) layer. This results in multi-scale quantum criticality in the coupled system. It is shown that the linear coupling between the two fields leads to a low energy fixed point characterized by the larger dynamical critical exponent z=3. The perturbative renormalization group is used to compute the correlation length in the quantum disordered and quantum critical regimes. We also derive the stochastic dynamics obeyed by the critical fluctuations in the quantum critical regime. Comparing the nonequilibrium situation to the thermal equilibrium scenario, where the whole system is at a temperature T, we find that the nonequilibrium drive does not always play the role of temperature.Comment: 20+ pages, 3 figures; Revised version as accepted by PRB, added figure of mean field phase diagra

Evolution of the single-hole spectral function across a quantum phase transition in the anisotropic-triangular-lattice antiferromagnet

We study the evolution of the single-hole spectral function when the ground state of the anisotropic-triangular-lattice antiferromagnet changes from the incommensurate magnetically-ordered phase to the spin-liquid state. In order to describe both of the ground states on equal footing, we use the large-N approach where the transition between these two phases can be obtained by controlling the quantum fluctuations via an 'effective' spin magnitude. Adding a hole into these ground states is described by a t-J type model in the slave-fermion representation. Implications of our results to possible future ARPES experiments on insulating frustrated magnets, especially Cs$_2$CuCl$_4$, are discussed.Comment: 8 pages, 7 figure

Molecular transistor coupled to phonons and Luttinger-liquid leads

We study the effects of electron-phonon interactions on the transport properties of a molecular quantum dot coupled to two Luttinger-liquid leads. In particular, we investigate the effects on the steady state current and DC noise characteristics. We consider both equilibrated and unequilibrated on-dot phonons. The density matrix formalism is applied in the high temperature approximation and the resulting semi-classical rate equation is numerically solved for various strengths of electron-electron interactions in the leads and electron-phonon coupling. The current and the noise are in general smeared out and suppressed due to intralead electron interaction. On the other hand, the Fano factor, which measures the noise normalized by the current, is more enhanced as the intralead interaction becomes stronger. As the electron-phonon coupling becomes greater than order one, the Fano factor exhibits super-Poissonian behaviour.Comment: 11 pages, 11 figure

Nonequilibrium quantum criticality in open electronic systems

A theory is presented of quantum criticality in open (coupled to reservoirs) itinerant electron magnets, with nonequilibrium drive provided by current flow across the system. Both departures from equilibrium at conventional (equilibrium) quantum critical points and the physics of phase transitions induced by the nonequilibrium drive are treated. Nonequilibrium-induced phase transitions are found to have the same leading critical behavior as conventional thermal phase transitions.Comment: 5 pages, 1 figur

The Effects of Visual Complexity in a Fashion Store Environment on Consumer Emotions and Approach Behavior

This study investigated the consumers\u27 affective response to the visual complexity of a fashion retail environment both self-report and psychophysiological measures. We developed two types of virtual fashion stores with different levels of visual complexity, which were manipulated using decorative patterns and type of layout (grid vs. free form). The results showed that the fashion store\u27s visual complexity was related to increases in arousal, but visual complexity has no main effect on pleasure. However, the moderating role of fashion involvement suggests that consumers with high fashion involvement exhibited more pleasure in a visually complex store than in a simple store. Additional analysis confirmed the moderated mediation effect of pleasure and mediation effect of arousal on relationships between stores\u27 visual complexity and store attractiveness. The research findings obtained through the psychophysiological measures enrich existing literature on visual complexity and provide theoretical and managerial implications