Backaction in metasurface etalons

We consider the response of etalons created by a combination of a conventional mirror and a metasurface, composed of a periodic lattice of metal scatterers with a resonant response. This geometry has been used previously for perfect absorption, in so-called Salisbury screens, and for hybridization of localized plasmons with Fabry-Perot resonances. The particular aspect we address is if one can assume an environment-independent reflectivity for the metasurface when calculating the reflectivity of the composite system, as in a standard Fabry-Perot analysis, or whether the fact that the metasurface interacts with its own mirror image renormalizes its response. Using lattice sum theory, we take into account all possible retarded dipole-dipole interactions of scatterers in the metasurface amongst each other, and through the mirror. We show that while a layer-by-layer Fabry-Perot formalism captures the main qualitative features of metasurface etalons, in fact the mirror modifies both the polarizability and reflectivity of the metasurface in a fashion that is akin to Drexhage's modification of the radiative properties of a single dipole.Comment: 10 pages, 5 figure

Spin Hall effect of light in photon tunneling

We resolve the breakdown of angular momentum conservation on two-dimensional photon tunneling by considering spin Hall effect (SHE) of light. This interesting effect manifests itself as polarization-dependent transverse shifts for a classic wave packet tunneling through a prism-air-prism barrier. For a certain circularly polarized component, the transverse shifts can be modulated by altering the refractive index gradient associated with the two prisms. We find that the SHE in conventional beam refraction can be evidently enhanced via photon tunneling mechanism. The polarization-dependent transverse shift is governed by the total angular momentum conservation law, while the polarization-dependent angular shift is governed by the total linear momentum law. These findings open the possibility for developing new nano-photonic devices and can be extrapolated to other physical systems.Comment: 8 pages, 5 figure

Statistical properties of spontaneous emission near a rough surface

We study the lifetime of the excited state of an atom or molecule near a plane surface with a given random surface roughness. In particular, we discuss the impact of the scattering of surface modes within the rough surface. Our study is completed by considering the lateral correlation length of the decay rate and the variance discussing its relation to the C0 correlation

Relação entre temperatura de pirólise e a porosidade do mesocarpo de frutos da castanheira-do-Brasil.

A casca dos frutos de castanhado-Brasil (Bertholletia excelsa) é um resíduo abundante, mas praticamente sem aproveitamento nas regiões extrativistas da Amazônia. Sendo assim, trata-se de uma matéria-prima com potencial para a produção de carvão para uso agronômico. Neste trabalho, avalia-se por meio de imagens de microscopia eletrônica de varredura o desenvolvimento da porosidade em carvões obtidos a partir das cascas dos frutos de castanheira-do-Brasil pirolisadas a 350, 450 e 550°C. Devido às particularidades morfológicas deste tecido vegetal, a porosidade do carvão aumenta com a temperatura, independente da fração granulométrica analisada

Relação entre temperatura de pirólise e a porosidade do mesocarpo de frutos da castanheira-do-Brasil.

A casca dos frutos de castanhado-Brasil (Bertholletia excelsa) é um resíduo abundante, mas praticamente sem aproveitamento nas regiões extrativistas da Amazônia. Sendo assim, trata-se de uma matéria-prima com potencial para a produção de carvão para uso agronômico. Neste trabalho, avalia-se por meio de imagens de microscopia eletrônica de varredura o desenvolvimento da porosidade em carvões obtidos a partir das cascas dos frutos de castanheira-do-Brasil pirolisadas a 350, 450 e 550°C. Devido às particularidades morfológicas deste tecido vegetal, a porosidade do carvão aumenta com a temperatura, independente da fração granulométrica analisada

Extrapolation-CAM Theory for Critical Exponents

By intentionally underestimating the rate of convergence of exact-diagonalization values for the mass or energy gaps of finite systems, we form families of sequences of gap estimates. The gap estimates cross zero with generically nonzero linear terms in their Taylor expansions, so that $\nu = 1$ for each member of these sequences of estimates. Thus, the Coherent Anomaly Method can be used to determine $\nu$. Our freedom in deciding exactly how to underestimate the convergence allows us to choose the sequence that displays the clearest coherent anomaly. We demonstrate this approach on the two-dimensional ferromagnetic Ising model, for which $\nu = 1$. We also use it on the three-dimensional ferromagnetic Ising model, finding $\nu \approx 0.629$, in good agreement with other estimates.Comment: 21 pages, Submitted to Journal of Physics A; new section added discussing rate of convergence and relation to Finite-Size Scalin

Replay: multi-modal multi-view acted videos for casual holography

We introduce Replay, a collection of multi-view, multimodal videos of humans interacting socially. Each scene is filmed in high production quality, from different viewpoints with several static cameras, as well as wearable action cameras, and recorded with a large array of microphones at different positions in the room. Overall, the dataset contains over 4000 minutes of footage and over 7 million timestamped high-resolution frames annotated with camera poses and partially with foreground masks. The Replay dataset has many potential applications, such as novelview synthesis, 3D reconstruction, novel-view acoustic synthesis, human body and face analysis, and training generative models. We provide a benchmark for training and evaluating novel-view synthesis, with two scenarios of different difficulty. Finally, we evaluate several baseline state-of-theart methods on the new benchmark

Working Papers, Open Access and Cyber-Infrastructure in Classical Studies

Princeton–Stanford Working Papers in Classics is a web-based series of work-in-progress scripts by members of two leading departments of classics. It introduces the humanities to a new form of scholarly communication and represents a major advance in the free availability of classical-studies scholarship in cyberspace. This article both reviews the initial performance of this open-access experiment and the benefits and challenges of working papers more generally for classical studies. After two years of operation Princeton–Stanford Working Papers in Classics has proven to be a clear success. This series has built up a large international readership and a sizeable body of preprints and performs important scholarly and community-outreach functions. As this performance is largely due to its congruency with the working arrangements of ancient historians and classicists and the global demand for open-access scholarship, the series confirms the viability of this means of scholarly communication and the likelihood of its expansion in our discipline. But modifications are required to increase the benefits this series brings and the amount of scholarship it makes freely available online. Finally departments wishing to replicate its success will have to consider other important developments, such as the increasing availability of postprints, the linking of research funding to open access, and the emergence of new cyber-infrastructure