Single shot cathode transverse momentum imaging in high brightness photoinjectors

In state of the art photoinjector electron sources, thermal emittance from photoemission dominates the final injector emittance. Therefore, low thermal emittance cathode developments and diagnostics are very important. Conventional thermal emittance measurements for the high gradient gun are time-consuming and thus thermal emittance is not measured as frequently as quantum efficiency during the lifetime of photocathodes, although both are important properties for the photoinjector optimizations. In this paper, a single shot measurement of photoemission transverse momentum, i.e., thermal emittance per rms laser spot size, is proposed for photocathode rf guns. By tuning the gun solenoid focusing, the electrons' transverse momenta at the cathode are imaged to a downstream screen, which enables a single shot measurement of both the rms value and the detailed spectra of the photoelectrons' transverse momenta. Both simulations and proof of principle experiments are reported

Quantum state engineering in hybrid open quantum systems

We investigate a possibility to generate nonclassical states in light-matter coupled noisy quantum systems, namely, the anisotropic Rabi and Dicke models. In these hybrid quantum systems, a competing influence of coherent internal dynamics and environment-induced dissipation drives the system into nonequilibrium steady states (NESSs). Explicitly, for the anisotropic Rabi model, the steady state is given by an incoherent mixture of two states of opposite parities, but as each parity state displays light-matter entanglement, we also find that the full state is entangled. Furthermore, as a natural extension of the anisotropic Rabi model to an infinite spin subsystem, we next explored the NESS of the anisotropic Dicke model. The NESS of this linearized Dicke model is also an inseparable state of light and matter. With an aim to enrich the dynamics beyond the sustainable entanglement found for the NESS of these hybrid quantum systems, we also propose to combine an all-optical feedback strategy for quantum state protection and for establishing quantum control in these systems. Our present work further elucidates the relevance of such hybrid open quantum systems for potential applications in quantum architectures

Beyond the Jaynes-Cummings model: circuit QED in the ultrastrong coupling regime

In cavity quantum electrodynamics (QED), light-matter interaction is probed at its most fundamental level, where individual atoms are coupled to single photons stored in three-dimensional cavities. This unique possibility to experimentally explore the foundations of quantum physics has greatly evolved with the advent of circuit QED, where on-chip superconducting qubits and oscillators play the roles of two-level atoms and cavities, respectively. In the strong coupling limit, atom and cavity can exchange a photon frequently before coherence is lost. This important regime has been reached both in cavity and circuit QED, but the design flexibility and engineering potential of the latter allowed for increasing the ratio between the atom-cavity coupling rate and the cavity transition frequency above the percent level. While these experiments are well described by the renowned Jaynes-Cummings model, novel physics is expected in the ultrastrong coupling limit. Here, we report on the first experimental realization of a superconducting circuit QED system in the ultrastrong coupling limit and present direct evidence for the breakdown of the Jaynes-Cummings model.Comment: 5 pages, 3 figure

The coherent interaction between matter and radiation - A tutorial on the Jaynes-Cummings model

The Jaynes-Cummings (JC) model is a milestone in the theory of coherent interaction between a two-level system and a single bosonic field mode. This tutorial aims to give a complete description of the model, analyzing the Hamiltonian of the system, its eigenvalues and eigestates, in order to characterize the dynamics of system and subsystems. The Rabi oscillations, together with the collapse and revival effects, are distinguishing features of the JC model and are important for applications in Quantum Information theory. The framework of cavity quantum electrodynamics (cQED) is chosen and two fundamental experiments on the coherent interaction between Rydberg atoms and a single cavity field mode are described.Comment: 22 pages, 7 figures. Tutorial. Submitted to a special issue of EPJ - ST devoted to the memory of Federico Casagrand

Quantum Simulation of Spin Chains Coupled to Bosonic Modes with Superconducting Circuits

We propose the implementation of a digital quantum simulation of spin chains coupled to bosonic field modes in superconducting circuits. Gates with high fidelities allows one to simulate a variety of Ising magnetic pairing interactions with transverse field, Tavis-Cummings interaction between spins and a bosonic mode, and a spin model with three-body terms. We analyze the feasibility of the implementation in realistic circuit quantum electrodynamics setups, where the interactions are either realized via capacitive couplings or mediated by microwave resonators.Comment: Chapter in R. S. Anderssen et al. (eds.), Mathematics for Industry 11 (Springer Japan, 2015

Effects of chemical modifications on photophysics and exciton dynamics of π -conjugation attenuated and metal-chelated photoconducting polymers.

Abstract Effects of two types of chemical modifications on photoconducting polymers consisting of polyphenylenevinylene (PPV) derivatives are studied by static and ultrafast transient optical spectroscopy as well as semi-empirical ZINDO calculations. The first type of modification inserts 2,2'-bipyridyl-5 -vinylene units (bpyV) in the PPV backbone, and the second type involves metal -chelation with the bpy sites. Photohuninescence and exciton dynamics of polymers 1 and 2 with PV:bpyV ratios of 1 and 3 were examined in solution, and compared to those of the homopolymer, poly(2,5-bis(2' -ethylhexyloxy)-l ,4-phenylenevinylene) (BEH-PPV), Similar studies were carried out for several metal-chelated polymers. These results can be explained by changes in n-conjugation throughout the polymer backbone. The attenuation in n-conjugation by the chemical modifications transforms a conducting polymer from one-dimensional semiconductor to molecular aggregates. Keywords poly(phenylene vinylene) derivatives, molecular aggregates, x-conjugation, time-resolved fast spectroscopy, chemical synthesis, semi-empirical and model calculations. Introduction In order to expand applications for conducting polymers, chemical modifications have been carried out by researchers l-s. These modifications may occur at the backbone or at the side groups of the polymers5'7-'0. In this study, the photophysics of two poly(phenylene vinylene) (PPV) derivatives which are chemically modified at the backbon

1994 turfgrass research report

Moss control on bentgrass greens evaluation / Jill Taylor -- Preemergent spotted spurge broadleaf weed control evaluation / William Pound and Renee Stewart -- Finale/Roundup herbicide demonstration evaluation / William Pound and Renee Stewart -- Turflon solvent evaluation / William Pound and Renee Stewart -- General turfgrass broadleaf weed control evaluation / William Pound and Renee Stewart -- Postemergence herbicide efficacy on crabgrass / John Street and Renee Stewart -- Preemergence herbicide efficacy on crabgrass / John Street, Jill Taylor and Renee Stewart -- Leaf spot control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Dollar spot control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Brown patch control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Anthracnose control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Summer patch control study / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Yellow tuft control study / Karl Danneberger, Joe Rimelspach and Jill Taylor -- Red thread control study, Columbus / Joe Rimelspach, Karl Danneberger and Jill Taylor -- Red thread control study, Delaware / Joe Rimelspach, Bobby Joyner, Joe Green and Jerry Sullivan -- Susceptibility of bentgrass cultivars to Fore+ Aliette combinations / Karl Danneberger and Jill Taylor -- Suppression of turf diseases with biocontrol agent fortified compost-amended topdressings / Marcella Grebus, Carol Musselman, Joe Rimelspach and Harry Hoitink -- Evaluation of fungicides for resistance to dollar spot (Sclerotinia homoecmpa) on creeping bentgrass / Joe Rimelspach, Jill Taylor and Karl Danneberger -- Application of an insect growth regulator and insecticide on baits for control of ant mounds in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Application of insecticides for control of black turfgrass ataenius larvae in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of biorationals and biologicals for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Evaluation of pyrethroids and other insecticides for control of black cutworm (Agrotis ipsilon Hufnagel) and sod webworm (Pyralidae, Crambinae) larvae in bentgrass, 1994 / David Shetlar, Harry Niemczyk and Kevin Power -- Surface and subsurface applied insecticides for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Influence of application time on the efficacy of insect growth regulators for control of white grubs in turfgrass / David Shetlar, Harry Niemczyk and Kevin Power -- Subsurface placement of controlled release chlorpyrifos granules for extended control of Japanese beetle larvae in turfgrass: third report / Harry Niemczyk and David Shetlar -- Evaluation of Turplex 3 % EC for control of black cutworm larvae on the greens of Shadow Creek Golf Course, N. Las Vegas, Nevada / Harry Niemczyk -- Nitrogen Source and Rate effect on Kentucky bluegrass / John Street and Renee Stewart -- Polymer-coated nitrogen source effect on Kentucky bluegrass / John Street and Renee Stewart -- Evaluation of turfgrass species and cultivars for shade / Jill Taylor -- Regional low input sustainable turf study / Jill Taylor -- 1990 NTEP perennial ryegrass test / Jill Taylor -- 1994 NTEP perennial ryegrass test / Jill Taylor -- 1993 NTEP bentgrass test (fairway/tee) / Jill Taylor -- 1993 NTEP fineleaf fescue test / Jill Taylor -- Bermudagrass management study / John Street and Jill Taylor -- Duration of rolling as measured by ball roll / Karl Danneberger, Jill Taylor and Jobin Morrow -- Golf ball roll as influenced by soft spike and traditional metal spike golf shoes / Karl Danneberger and Jobin Morrow -- Primo/Banner interaction study / Bill Pound, Renee Stewart and Joe Rimelspach -- Primo growth regulator evaluation on creeping bentgrass / William Pound and Renee Stewart -- Restriction of arbitrary amplification fragments of Poa annua L. / Patty Sweeney and Karl Danneberge

Quantum Acoustics with Surface Acoustic Waves

It has recently been demonstrated that surface acoustic waves (SAWs) can interact with superconducting qubits at the quantum level. SAW resonators in the GHz frequency range have also been found to have low loss at temperatures compatible with superconducting quantum circuits. These advances open up new possibilities to use the phonon degree of freedom to carry quantum information. In this paper, we give a description of the basic SAW components needed to develop quantum circuits, where propagating or localized SAW-phonons are used both to study basic physics and to manipulate quantum information. Using phonons instead of photons offers new possibilities which make these quantum acoustic circuits very interesting. We discuss general considerations for SAW experiments at the quantum level and describe experiments both with SAW resonators and with interaction between SAWs and a qubit. We also discuss several potential future developments.Comment: 14 pages, 12 figure

Turfgrass research report 1996

Preemergence herbicide efficacy on crabgrass-1996 / J. Street and R. Stewart --Postemergence herbicide efficacy on crabgrass -1996 / J. Street and R. Stewart -- General turfgrass broadleaf weed control evaluation / W. Pound -- Nonselective herbicide evaluation / W. Pound -- Postemergent yellow nutsedge evaluation / W. Pound and R. Stewart -- Preemergent broadleaf weed control / W. Pound -- Control of ant mounds in turfgrass-1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Control of hairy chinch bugs in turfgrass -1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Preventive and curative insecticide applications for control of hairy chinch bugs in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Quick kill of black cutworm larvae in bentgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Control of black cutworm, Agrotis ipsilon (Hufnagel), and sod webworms (Pyralidae: Crambinae) in creeping bentgrass, Agrostis palustris Hudson, with spinosad formulations, Columbus, Ohio, 1996 / D. J. Shetlar, H. D. Niemczyk and M. Belcher -- Control of black cutworm, Agrotis ipsilon (Hufnagel), and sod webworms (Pyralidae: Crambinae) in creeping bentgrass, Agrostis palustris Hudson, with observations on black turfgrass Ataenius adults, Ataenius spretulus (Haldeman), Columbus, Ohio, 1996 / D. J. Shetlar, H. D. Niemczyk and M. Belcher -- Control of black cutworm, Agrotis ipsilon (Hufnagel), sod webworms (Pyralidae: Crambinae), and black turfgrass Ataenius adults, Ataenius spretulus (Haldeman), in creeping bentgrass, Agrostis palustris Hudson, Columbus, Ohio, 1996 / D. J. Shetlar, H. D. Niemczyk and M. Belcher -- Control of bluegrass billbug, Sphenophorus parvulus Gyllenhal, larvae in lawn turf, Wooster, Ohio, 1996 / D. J. Shetlar, H. D. Niemczyk and M. Belcher -- Efficacy of spinosad applied prior to oviposition for control of bluegrass billbug larvae in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Efficacy of insecticides applied prior to oviposition for control of bluegrass billbug larvae in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Application of insecticides to kill black turfgrass Ataenius adults prior to egg laying on golf course fairways-1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Preventive applications for control of Japanese beetle larvae in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Influence of application date on the efficacy of insecticides applied for control of Japanese beetle larvae in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Application of insecticides for preventive control of Japanese beetle larval populations in turfgrass - 1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Application of Bacillus thuringiensis strain 'buibui' for control of white grubs in turfgrass -1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- Curative control of masked chafer larvae in turfgrass -1996 / D. J. Shetlar, H. D. Niemczyk and K. T. Power -- A field test of RH-0345 2SC and 2.5G at 2.0 lb.ai/ acre and Merit 75WP at 0.3 lb. ai/ acre for control of black cutworm larvae on golf course greens / H. D. Niemczyk -- Dollar spot control study - 1996 / K. Danneberger, J. Rimelspach, M. Boehm, and J. Taylor -- quality ratings for various fungicide treatments on creeping bentgrass putting green turf / K. Danneberger, J. Rimelspach, M. Boehm, and J. Taylor -- Brown patch control study on creeping bentgrass turf - 1996 / K. Danneberger, J. Rimelspach, M. Boehm, and J. Taylor -- Brown patch control on tall fescue / K. Danneberger, J. Rimelspach, M. Boehm, and J. Taylor -- Yellow tuft study-1996 / K. Danneberger, J. Rimelspach, M. Boehm, and J. Taylor -- Creeping bentgrass melting-out study / K. Danneberger, J. Taylor, R. Golembiewski, G. Bell, J. Rimelspach, and M. Boehm -- Kentucky bluegrass melting-out study / K. Danneberger, J. Rimelspach, M. Boehm and J. Taylor -- Red thread control study on perennial ryegrass / J. Rimelspach, K. Danneberger, and M. Boehm -- Red thread control study on Kentucky bluegrass / J. Rimelspach, K. Danneberger and M. Boehm -- Evaluation of fungicides for the control of red thread in Kentucky bluegrass, 1996 / J. Rimelspach, M. Boehm, K. Danneberger and J. Taylor -- Evaluation of fungicides for the control of red thread in perennial ryegrass, 1996 / J. Rimelspach, M. Boehm, K. Danneberger and J. Taylor -- Pink snow mold control study-1995-1996 / J. Rimelspach and K. Danneberger -- Primo & Sentinel applications on Poa annua quality / K. Danneberger, J. Taylor, R. Golembiewski, and G. Bell -- Nitrogen source, rate, and timing effect on Kentucky bluegrass -1996 / J. R. Street and R. M. Stewart -- Natural organic source evaluation on a Kentucky bluegrass-perennial ryegrass mixture-1996 / J. R. Street and R. M. Stewart -- Polymer-coated urea source and rate effect on Kentucky bluegrass / J. R. Street and R. M. Stewart -- Polymer-coated urea and IBDU fertilizer performance on Kentucky bluegrass / J. R. Street and R. M. Stewart -- 1993 NTEP bentgrass (fairway/tee) cultivar evaluation / J. A. Taylor -- 1993 NTEP fineleaf fescue cultivar evaluation / J. Taylor -- 1994 NTEP perennial ryegrass cultivar evaluation / J. Taylor -- 1995 Kentucky bluegrass (medium/high input) cultivar evaluation / J. Taylor -- 1995 NTEP Kentucky bluegrass (low input) cultivar evaluation / J. Taylor -- Controlling annual bluegrass and rough bluegrass in creeping bentgrass fairways: a nutritional approach / G. E. Bell, E. Odorizzi and T. K. Danneberger -- "Primo" growth regulator evaluation on creeping bentgrass / W. Pound and R. Stewart -- Influence of dollar spot on a blend of two creeping bentgrass cultivars / R. C. Golembiewski, T. K. Danneberger and P. M. Sweeney -- Dollar spot severity as influenced by Primo, creeping bentgrass cultivars, and nitrogen fertility / R. C. Golembiewski and T. K. Danneberger -- Identification of bulk samples of perennial ryegrass cultivars with RAPD Markers / P. M. Sweeney and T. K. Danneberge

Emittance Reduction of RF Photoinjector Generated Electron Beams by Transverse Laser Beam Shaping

Laser pulse shaping is one of the key elements to generate low emittance electron beams with RF photoinjectors. Ultimately high performance can be achieved with ellipsoidal laser pulses, but 3-dimensional shaping is challenging. High beam quality can also be reached by simple transverse pulse shaping, which has demonstrated improved beam emittance compared to a transversely uniform laser in the 'pancake' photoemission regime. In this contribution we present the truncation of a Gaussian laser at a radius of approximately one sigma in the intermediate (electron bunch length directly after emission about the same as radius) photoemission regime with high acceleration gradients (up to 60 MV/m). This type of electron bunch is used e.g. at the European XFEL and FLASH free electron lasers at DESY, Hamburg site and is being investigated in detail at the Photoinjector Test facility at DESY in Zeuthen (PITZ). Here we present ray-tracing simulations and experimental data of a laser beamline upgrade enabling variable transverse truncation. Initial projected emittance measurements taken with help of this setup are shown, as well as supporting beam dynamics simulations. Additional simulations show the potential for substantial reduction of slice emittance at PITZ. © Published under licence by IOP Publishing Ltd