Induced Coherence and Stable Soliton Spiraling

We develop a theory of soliton spiraling in a bulk nonlinear medium and reveal a new physical mechanism: periodic power exchange via induced coherence, which can lead to stable spiraling and the formation of dynamical two-soliton states. Our theory not only explains earlier observations, but provides a number of predictions which are also verified experimentally. Finally, we show theoretically and experimentally that soliton spiraling can be controled by the degree of mutual initial coherence.Comment: 4 pages, 5 figure

MetaPOAP: Presence or Absence of Metabolic Pathways in Metagenome-Assembled Genomes

Genome-resolved metagenomics allows the construction of draft microbial genomes from short-read shotgun metagenomics (Metagenome-Assembled Genomes, or MAGs); however, even high-quality MAGs are typically somewhat incomplete and contain a small amount of contaminant sequence, making accurate prediction of metabolic potential challenging. Here, we describe MetaPOAP, an algorithm for probabalistic assessment of the statistical likelihoods for the presence or absence of metabolic pathways in MAGs

Evolution of Phototrophy in the Chloroflexi Phylum Driven by Horizontal Gene Transfer

The evolutionary mechanisms behind the extant distribution of photosynthesis is a point of substantial contention. Hypotheses range from the presence of phototrophy in the last universal common ancestor and massive gene loss in most lineages, to a later origin in Cyanobacteria followed by extensive horizontal gene transfer into the extant phototrophic clades, with intermediate scenarios that incorporate aspects of both end-members. Here, we report draft genomes of 11 Chloroflexi: the phototrophic Chloroflexia isolate Kouleothrix aurantiaca as well as 10 genome bins recovered from metagenomic sequencing of microbial mats found in Japanese hot springs. Two of these metagenome bins encode photrophic reaction centers and several of these bins form a metabolically diverse, monophyletic clade sister to the Anaerolineae class that we term Candidatus Thermofonsia. Comparisons of organismal (based on conserved ribosomal) and phototrophy (reaction center and bacteriochlorophyll synthesis) protein phylogenies throughout the Chloroflexi demonstrate that two new lineages acquired phototrophy independently via horizontal gene transfer (HGT) from different ancestral donors within the classically phototrophic Chloroflexia class. These results illustrate a complex history of phototrophy within this group, with metabolic innovation tied to HGT. These observations do not support simple hypotheses for the evolution of photosynthesis that require massive character loss from many clades; rather, HGT appears to be the defining mechanic for the distribution of phototrophy in many of the extant clades in which it appears

Quantum teleportation between moving detectors in a quantum field

We consider the quantum teleportation of continuous variables modeled by Unruh-DeWitt detectors coupled to a common quantum field initially in the Minkowski vacuum. An unknown coherent state of an Unruh-DeWitt detector is teleported from one inertial agent (Alice) to an almost uniformly accelerated agent (Rob, for relativistic motion), using a detector pair initially entangled and shared by these two agents. The averaged physical fidelity of quantum teleportation, which is independent of the observer's frame, always drops below the best fidelity value from classical teleportation before the detector pair becomes disentangled with the measure of entanglement evaluated around the future lightcone of the joint measurement event by Alice. The distortion of the quantum state of the entangled detector pair from the initial state can suppress the fidelity significantly even when the detectors are still strongly entangled around the lightcone. We point out that the dynamics of entanglement of the detector pair observed in Minkowski frame or in quasi-Rindler frame are not directly related to the physical fidelity of quantum teleportation in our setup. These results are useful as a guide to making judicious choices of states and parameter ranges and estimation of the efficiency of quantum teleportation in relativistic quantum systems under environmental influences.Comment: 18 pages, 7 figure

Batalin-Vilkovisky Integrals in Finite Dimensions

The Batalin-Vilkovisky method (BV) is the most powerful method to analyze functional integrals with (infinite-dimensional) gauge symmetries presently known. It has been invented to fix gauges associated with symmetries that do not close off-shell. Homological Perturbation Theory is introduced and used to develop the integration theory behind BV and to describe the BV quantization of a Lagrangian system with symmetries. Localization (illustrated in terms of Duistermaat-Heckman localization) as well as anomalous symmetries are discussed in the framework of BV.Comment: 35 page

New high-efficiency source of photon pairs for engineering quantum entanglement

We have constructed an efficient source of photon pairs using a waveguide-type nonlinear device and performed a two-photon interference experiment with an unbalanced Michelson interferometer. Parametric down-converted photons from the nonlinear device are detected by two detectors located at the output ports of the interferometer. Because the interferometer is constructed with two optical paths of different length, photons from the shorter path arrive at the detector earlier than those from the longer path. We find that the difference of arrival time and the time window of the coincidence counter are important parameters which determine the boundary between the classical and quantum regime. When the time window of the coincidence counter is smaller than the arrival time difference, fringes of high visibility (80$\pm$ 10%) were observed. This result is only explained by quantum theory and is clear evidence for quantum entanglement of the interferometer's optical paths.Comment: 4 pages, 4 figures, IQEC200

The Structure of a Langmuir Monolayer of Methyl Eicosanoate as Determined by X‐Ray Diffraction and Brewster Angle Microscopy

Relaxed Langmuir monolayers of methyl eicosanoate were studied using Brewster angle microscopy (BAM) and grazing incidence x‐ray diffraction (GIXD). The structure of the various phases in this system was determined and compared to previous isotherm and microscopy measurements. At low pressure and low temperature, a crystalline phase with tilt toward nearest neighbor, I($L^{\prime\prime}_{2}$), is observed. At a temperature of $\sim$14$^\circ$C and low pressure there is a transition to a phase with tilt toward next‐nearest neighbor, F($L^{\prime}_{2}$). Finally, as the temperature continues to be raised at low pressure, there is a transition to a phase where the two F($L^{\prime}_{2}$) peaks have the same values of $Q_{xy}$, here called the $\tau$ phase, with a Rotator IV‐like structure. At high pressure and low temperature, an untilted, orthorhombic phase, $U^{\prime}$(CS), is observed. As the temperature is increased, a second untilted, orthorhombic phase, U(S), is observed, beginning at $\sim$12$^\circ$C. Above 21$^\circ$C and at high pressure, a Rotator‐II‐like phase is seen, with an undistorted, untilted structure. Finally, results from BAM measurements are used to monitor the texture of the film in the different phases.Engineering and Applied Science