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As microelectronics evolves into nanoelectronics with faster switching speeds and the associated energy dissipation, determining local temperature and temperature gradients becomes an increasingly important challenge for solving design and manufacturing problems as well as improving reliability. Recently, experimental studies of low-temperature quantum thermal phenomena, in which heat is ruled by quantum physics, have been developing at an ever-increasing pace. A fundamental issue posed by finite temperatures is spontaneous fluctuations of electric currents occurring inside electrical conductors even in equilibrium, regardless of any applied voltage (the Johnson-Nyquist noise). Recently, a new (previously overlooked) non-equilibrium contribution to noise in a temperature-biased nanoscale conductive structure was discovered and called delta-T noise. In this paper, we argue that, along with stationary characteristics, both techniques can be successfully used to reveal on-surface dynamic processes in a cryogenic environment when other thermodynamic techniques lose sensitivity or cease to operate. Our calculations based on the scattering theory of nonlinear ac electron quantum transport show that related frequency-dependent noise spectra and their derivatives over frequency directly reflect the amplitude and the frequency of periodic current fluctuations. For practical implementations, it is proposed to use a multi-tip scanning tunneling microscope technique, which in our case needs only two tips, in contrast to the four-contact probing currently being implemented. Such nanoscale measurements, which are most effective at cryogenic temperatures, can provide important information about local thermally induced nanoscale processes useful for such applications as nanoelectronics and sensing technologies.

We (re)consider how the Fukaya category of a Lefschetz fibration is related to that of the fiber. The distinguishing feature of the approach here is a more direct identification of the bimodule homomorphism involved.

Non-destructive measurements of nA beam currents in particle beam storage rings by detecting the azimuthal magnetic field generated by moving charged particles with a Cryogenic Current Comparator (CCC) are well established. The detection of beam currents with small amplitudes with a CCC in a storage ring demands a high slew rate which is caused by the rapid change of the beam current exceeding the operational limit of the SQUID in flux-locked loop mode. Previous solutions to increase the slew rate used a LCR first-order low-pass filter were a small resistor, unfortunately, dominated the current noise of the CCC. In this work we present a novel take by adding a second resonator into the CCC which in turn allows for higher resistances of the LCR low-pass filter and therefore lower thermal current noise. A second challenge connected with this CCC approach is the residual magnetization of the highly permeable magnetic core and the resulting shielding currents in the superconducting circuits of the CCC. The timing of a storage ring in the range of minutes opens a way to reduce these DC currents using a LR high-pass filter. Using serial sub-micro ohm resistors, time constants in the hour range can be achieved to improve the stability and performance of the CCC system.

Time-dependent electron current through a nanoscale phase-coherent quantum ring with leads, coupled to reservoirs biased by a sinusoidal voltage, is studied. We argue that Floquet states in such samples, driven also by external time-periodic magnetic field, can be coherently manipulated. Some examples show that on-demand structures in the frequency domain, tunable by the joint action of the voltage bias and a microwave pumping, can be generated this way.

Understanding electronic noise in hybrid junctions is essential for designing efficient nanoscale electronics at the quantum limit. Recently, a new (previously overlooked) noise contribution, generated by the temperature difference across a conducting heterostructure and denoted as delta-T noise, was predicted and revealed experimentally in atomic-scale contacts (Shein Lambroso et al. in Nature 562:240–244, 2018). While the new type of electronic noise and the well-known voltage-generated shot noise have the same partition origin, they are activated by different stimuli. In the paper by Shein Lambroso et al. (2018), transmission probabilities for electrons flowing through the considered setups were assumed to be constant, a very good approximation for normal metal contacts within the used temperature range. In this work, we propose and study theoretically the delta-T noise in hybrid normal metal–superconductor nanojunctions where it has to be more pronounced at low temperatures due to the strongly nonlinear energy dependence of interface scattering characteristics in the gap region. Such experiments can be useful to probe quantum effects and to reveal small temperature variations along electronic nanoscale circuits.

We consider the Fukaya-Floer $A_\infty$-structures arising from a basis of thimbles in a Lefschetz fibration. Particular attention is paid to the relation between these structures in the total space of the fibration, and their counterparts in the fibre.

Drastic events such as pandemics, earthquakes or other disasters threaten not only the immediate living conditions of people but also indirect circumstances such as energy supply, infrastructure and food production. To ensure that damage and failures in these areas do not lead to a disaster, special requirements are placed on this critical infrastructure. In this context resilience, which is defined as the resistance of a system to external effects, is required. A field that is indeed part of the critical infrastructure, but which has not been considered as intensively as the energy sector, is food production. The investigation focuses on how fundamental principles of thermodynamics, system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of resilience. Using known state and process variables from thermodynamics and electrical power engineering, analogous variables are derived for the food industry. These variables serve as an evaluation standard for a quality measure Q . In addition to system-theoretical considerations, it is investigated how existing evaluation criteria of power engineering, such as System Average Interruption Duration Index (SAIDI) and Customer Average Interruption Duration Index (CAIDI), can be transferred to food production. Design: The investigation focuses on how fundamental principles of thermodynamics, system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of resilience. Using known state and process variables from thermodynamics and electrical power engineering, analogous variables are derived for the food industry. Purpose: Drastic events such as pandemics, earthquakes or other disasters threaten not only the immediate living conditions of people but also indirect circumstances such as energy supply, infrastructure and food production. To ensure that damage and failures in these areas do not lead to a disaster, special requirements are placed on this critical infrastructure. In this context resilience is required. Findings: The aforementioned state and process variables serve as an evaluation standard for a quality measure Q. In addition to system-theoretical considerations, it is investigated how existing evaluation criteria of power engineering, such as SAIDI and CAIDI, can be transferred to food production. Originality: This paper fulfils an identified need to study a part of the critical infrastructure that has not been as extensively looked at as the energy sector, namely food production.

ZusammenfassungStudierende der Humanmedizin müssen sich im Rahmen ihrer universitären Ausbildung ein umfangreiches Wissen zunächst aus den Grundlagenwissenschaften und später aus den verschiedensten medizinischen Fachgebieten aneignen. Für Vertiefungen, insbesondere in kleinere, aber dennoch hochinteressante Fachbereiche − etwa der Nuklearmedizin – bleibt dabei oft wenig Zeit. Eine Option, Vertiefungen über den in Seminaren und Vorlesungen vermittelten, vorwiegend klinisch orientierten Stoff zu ermöglichen, bieten Wahlfächer. Die Klinik und Poliklinik für Nuklearmedizin des Universitätsklinikums Leipzig hat in diesem Jahr ein zusätzliches Wahlfach etabliert („Nuklearmedizin universal“), welches v. a. auf die Vermittlung des interdisziplinären Zusammenwirkens von Ärzten, Radiochemikern, Medizinphysikern/-technikern und Medizinisch-technischen Assistenten innerhalb der Nuklearmedizin abzielt. Das entsprechende Curriculum sowie die ersten Erfahrungen werden beschrieben und reflektiert.

Quantum entanglement is among the main fundamental resources for quantum information processing tasks like quantum communication, quantum computation, etc. The states with such kind of a nonlocal correlation can easily be obtained from a single-mode wave packet using a passive linear beam splitter. Taking into account scalable arguments and thus the need to implement quantum technologies in a solid-state platform, we study transmission of quantum data encoded in quasiparticles charges across a nanoscale three-arm beam splitter made by different BCS superconducting wires with a node size less than the smallest coherence length. It is calculated as to how a quasiparticle wave packet injected into one of the device leads is divided between two others. We show that an appropriate choice of the incoming wave packet permits to control the ratio of the two outgoing charges by comparatively small voltages of the order of the superconducting energy gap. The response of the device is analyzed as a function of the applied voltage biases and an asymmetry parameter, the ratio of the energy gaps in the two outward leads. We discuss two possible ways of the coherent wave-packet injection, specific pulses of voltages at ultra-low temperatures and those of current biases at temperatures comparable with the critical temperature of a superconducting emitter. Finally, we argue that voltages applied to outward leads as well as the temperature of an inward lead can serve as a control parameter for the charges delivered within a quantum network.

This paper presents c-direction hybrid Josephson junctions with base electrodes of Co:BaFe2As2 single crystals. To realize Josephson junctions, it applies standard photolithography technologies and a newly developed surface polishing method that was used. As conventional isotropic s-wave superconductor counter electrodes used double layers of Pb/In. The artificial barrier for the tunneling junctions consists of a thin sputtered Ti layer or a thermally evaporated Al layer; both layers were used as an insulator barrier. For characterizing the Josephson effects with TiOx barrier, we could realize IcRN products of about 13.7 μV and unconventional Ic-T dependencies. The formation of Shapiro steps under the influence of microwave irradiation and magnetic field to the junctions will be discussed as well.

Floer cohomology groups are usually defined over a field of formal functions (a Novikov field). Under certain assumptions, one can equip them with connections, which means operations of differentiation with respect to the Novikov variable. This allows one to write differential equations for Floer cohomology classes. Here, we apply that idea to symplectic cohomology groups associated to Lefschetz fibrations, and obtain a relation with enumerative geometry., v2: added a section describing the relation with equivariant symplectic cohomology; v3: typos removed, very minor expository changes; v4: even less typos

Floer homology is a version of Morse theory for certain infinite-dimensional spaces. Morse theory and Floer homology are examples of topological field theories in dimensions one and two, respectively. This chapter focuses on certain infinite-dimensional manifolds which carry natural Morse functions which have infinite Morse indices. It looks at some examples heuristically using finite-dimensional approximations. The “homology groups” which are obtained in this way do not describe the topology of the underlying space in the ordinary sense. The chapter discusses Morse theory from a different point of view, namely, as an example of a general strategy for producing topological invariants of manifolds. It also discusses Floer’s construction of homology groups, which is very similar to the approach to Morse theory. The chapter considers Floer homology for a rather different functional, namely, the Chern-Simons functional on gauge equivalence classes of connections on a three-manifold.

In the context of the energy transition in Germany energy-optimized and resource-saving buildings and building systems are being installed. To be able to do this, it is necessary to obtain information from the buildings, such as peak or base load of heating/cooling and electrical consumption. In the following publication a developed short-term analysis system based on a modular non-invasive measurement system will be described. Additional first results from a field test will be presented.

The numerical model of long Josephson junctions with Gaussian spread of critical currents has been developed. The model allowed calculating the IV-characteristics and power of emission of long junctions. Zero-field steps in IV-characteristics in the hysteretic region were found. When the spread of critical currents was comparable with the value of the averaged critical current, particularities corresponded to zero-field steps were found in the derivative of the IV-characteristic far above the hysteretic region. Results were qualitatively explained in ranges of the existing theory of zero-field steps in IV-curves of Josephson junctions with random distributions of critical currents. The model was applied for the approximation of particularities in the derivative of the earlier measured IV-curve of the heterostructure consisted of two superconducting electrodes made up of molybdenum-rhenium alloy and a hybrid semiconductor tunnel barrier with a nanosized silicon layer which contained tungsten nanoclusters [the MoRe-Si(W)-MoRe heterostructure]. The model described adequately positions of particularities in the derivative of the IV-characteristic in the wide range of voltages.

The superconducting transition temperature of 140 nm ± 10 nm thin films on sapphire substrates, which were deposited by magnetron sputtering, was around 36 K. Using a magnetization technique, the film's critical current density was estimated as J C = 1.8 × 107 А/cm2 at 10 K, J C = 8 × 106 А/m 2 at 20 K in a zero magnetic field B, and J C = 3 × 106 А/m2 at 10 K and B = 5 T. The values of the upper critical magnetic field B c2 and the irreversibility field B irr estimated using the four-probe technique were B C2(22 K) = 15 T when H||film surface, 11 T when H⊥film surface, and B irr(22 K) = 11 T when H||film surface. The X-ray study showed that the microstructure of the film contains only MgB2 and MgO (in minority). The SEM and EPXMA study and quantitative Auger spectroscopy analysis revealed periodical variations of the film composition on the nanolevel and the presence of (mainly) two intercalated Mg-B-O-C phases of slightly different, especially in oxygen content, and thus with different conductivity and, possibly, with different T C. The characteristics of superconducting magnesium diboride films make them promising for application in electronic devices, e.g., as high-pass filters.

Using simplified models, we have demonstrated how a single-electron wave packet can be engineered to realize directional and controlled transfer of quantum information across superconducting networks. A scheme to design different (energetically allowed) outcomes by tuning a single characteristic parameter of the driven pulse is proposed. We have identified an optimal wave packet generated by a normal emitter and study, as an example, the dynamics of its adiabatic quantum pumping into a single superconducting lead and two superconducting branches of a hybrid Y-shaped beam splitter. Finally, a short discussion concerning realization of electron sources able to emit desired wave packets carrying a single electron charge is given.

The new version of a cryogenic current comparator with eXtended dimensions (CCC-XD) for the beam monitoring of charged particles, which is currently in the optimization cycle, is presented herein. The CCC-XD is designed for a nondestructive, highly sensitive monitoring of a few nA beam intensities for 150-mm beamline diameters at the Facility for Antiproton and Ion Research at GSI (Helmholtz Center of Heavy Ion Research). The new CCC comprises a combined superconducting pickup loop, a magnetic shield, and a ferrite core with superconducting quantum interference device based readout. Compared to the previous CCC currently running at CERN, the niobium shield exhibits enlarged geometric dimensions, which results in a more effective suppression of magnetic stray fields from the beamline environment. First results of laboratory measurements as well as simulations of the electrical behavior are presented in this paper. The CCC-XD system—in combination with a newly developed cryostat—will be ready for testing in the beamline of CRYRING at GSI in 2018.

In order to study the origin of coherent emission of intrinsic junctions in high-temperature superconductors, we investigated numerically ac power of emission at zero-field steps in IV-characteristics of a stack of two inductively coupled long Josephson junctions as well as emission from the solitary long junction. We found that zero-field steps appeared due to noise, random distribution of critical currents or due to normal edges of junctions in the stack. Due to the formation of collective excitations in the stack of coupled junctions, the zero-field step was split into two steps, which correspond to two normal modes of excitations. We investigated the dependence of heights of steps on the length of the stack and found that there existed two different threshold values of the length, so above the threshold length the zero-field step existed and below the threshold length it vanished. We calculated the dependence of ac power on the length of the stack and found the optimal value of the length for larger emission.

Coherent charge and spin transport of entangled electron waves across a three-terminal setup formed by a charge emitter and two drain wires with a superconducting inset in one of them and a perfect absorber or a spin filter in the other is theoretically discussed. We show that self-controlled charge and spin currents across the device can be realized by employing highly nonlinear dispersion relation in the near-gap energy range of a superconductor.

The critical current density at 4.2 and 20 K up to 15 T and the temperature dependence of the irreversible field have been studied in magnesium diboride wires and bulks prepared from boron without and with carbon addition. Structural investigations using X-ray microprobe analysis have been performed. A monofilamentary wire with a round-shaped core manufactured from boron containing 2 mol.% carbon (approximate composition of its matrix MgB1.8–2.4O0.04–0.71C0.12–0.16) demonstrated Jc(20 K, 2 T) = 105 A/cm2 , Jc(4.2 K, 15 T) = 2 × 103 A/сm 2 and Birr (20 K) = 8 T, Birr(12.5 K) = 15 T. Bulk material synthesized at 2 GPa, 600 °C, 1 h from carbon doped boron demonstrated Jc(10 K, 10 T) = 4 × 103 A/сm 2 and Jc(20 K, 6 T) = 4 × 103 A/сm 2

The decommissioning of nuclear power plants and the storage of nuclear waste are major challenges for all nuclear countries. Both processes are technologically and financially challenging. We provide an analysis of the status quo of both processes in three major nuclear countries: Germany, France, and the U.K. Germany was able to gain some decommissioning experiences but not one large-scale reactor has been released from regulatory control. EDF was forced to cancel its target to immediately dismantle all GCRs by 2036 due to underestimated technological challenges, while in the U.K., decommissioning of the legacy fleet lasts well into the 22nd century. Until now, no scale effects could be observed, if EDF can reap scale effects due to the standardization of its fleet remains to be seen. The search for a deep geological disposal facility is the most advanced in France, where the start date is fixed by law to 2025. There are many uncertainties related to estimated future costs. In the three countries, three different funding schemes are implemented: Germany switched from internal non-segregated funds to an external segregated fund for waste management. In the U.K. the decommissioning of the legacy fleet will be paid by the taxpayer for the next 100 years while an external segregated fund was established for the current operational fleet. In France, an internal segregated fund finances the future liabilities of EDF.

We prepared SIS' (insulating barrier I, different superconducting electrodes S, and S') hybrid Josephson junctions on the polished surface of Ba-122 single crystals as a base electrode and used Pb as a thin-film counter electrode. We obtained $I_{c}R_{N}$ -products up to 1.15 mV and got remarkable $I_{c}R_{N}\mbox{-}T$ dependence. The influence of microwave irradiation to the junctions will be discussed.

We start with a short look at the problem of low-capacitance Josephson junctions, its history, and actual state-of-the-art. It is argued that such devices are important for applications requiring nonhysteretic current-voltage characteristics since reduction of capacitance by several times makes it possible to increase the device resistance by the same amount while keeping the McCumber-Stewart damping parameter unaltered. Moreover, at very high frequencies the capacitance in the RCSJ circuit with a parallel connection starts to shunt the superconducting current component due to reduction of the corresponding reactance inversely proportional to C. Hence, to extend the operating frequency range of a Josephson junction its capacitance should be as small as possible. As a solution of a new type of the Josephson device, less resistive and with smaller capacitance, we propose and realize a submicron-sized trilayer with tens nm-thick Si interlayer doped by metallic ultra-small inclusions and superconducting Mo-Re alloy electrodes.

We consider ℂ*-actions on Fukaya categories of exact symplectic manifolds. Such actions can be constructed by dimensional induction, going from the fibre of a Lefschetz fibration to its total space. We explore applications to the topology of Lagrangian submanifolds, with an emphasis on ease of computation., National Science Foundation (U.S.) (Grant DMS-1005288), National Science Foundation (U.S.) (Grant DMS-1500954), Simons Foundation (Simons Investigator Award)

We prepared planar hybrid Josephson junctions using Co-doped BaFeAs thin films and polished single crystals as base electrode, sputtered, and subsequently oxidized titanium layers as barrier and a counter electrode from evaporated lead. On all junctions, RCSJ-like current–voltage characteristics could be observed. The obtained products at 4.2 K range up to 95V for thin film junctions and up to 1.15 mV for junctions on single crystals. For most of the junctions, an excess current with variable contribution to the total current could be observed. Unusual temperature dependencies are discussed for the critical and the excess currents, respectively. Investigations of the junctions under microwave irradiation were performed, therein Shapiro steps up to high orders and very clear modulations of the steps could be observed. Additionally, the origin of the excess current is discussed with respect to the microwave dependence. Furthermore, instead of a single junction, a network-like modulation behavior of the critical current in magnetic fields was observed.

Consider cotangent bundles of exotic spheres with their canonical symplectic structure. They admit automorphisms that preserve the part at infinity of one fiber and which are analogous to the square of a Dehn twist. Pursuing that analogy, we show that they have infinite order up to isotopy (inside the group of all automorphisms with the same behavior)., Simons Foundation (Simons Investigator Grant), National Science Foundation (U.S.) (Grant DMS-1005288)

A Cryogenic Current Comparator (CCC) is a new type of instruments for monitoring charged beams like ions or antiprotons. Using superconducting effects is it possible to create a nondestructive, contactless and easy to calibrate beam measurement system with a high current resolution in amplitude and time. The Meissner effect enables an effective magnetic shielding of the system. The screening current enables creation of DC-transformers and therefore a DC-current measurement system. The combination of two Josephson-junctions and coils form a superconducting quantum interference device (SQUID) in an analog magnetic feedback of the flux-locked loop (FLL), which is linearizing the SQUID’s transfer function. The performance of the CCC system opens beam currents range between 1 nA and 20 µA. Installations at the Antiproton Decelerator at CERN and GSI in Darmstadt shows a strong correlation between SEM/longitudinal-Schottky and CCC signals including the known spill pattern but with a better signal to noise ratio.

Due to high values of energy gaps of high-temperature superconductors, wavelengths of Josephson generation of intrinsic Josephson junctions in these superconductors are in the range from several tens of micrometers to hundreds micrometers. Therefore, high-temperature superconductors are promising sources of submilimeter waves. Linear dimensions of samples of intrinsic Josephson junctions are inside this range of wavelengths. Because of the influence of modes of geometrical resonances, self-induced steps (so-called zero-field steps) appear in IV-characteristics of samples. We studied numerically the phase locking phenomenon at zero-field steps. We developed a model of a long junction in which the long junction is divided to a number of small parts. We investigated IV-characteristics and stability of the solution of dynamic equations of all parts of one separate long intrinsic junction with homogeneous distribution of critical currents. Our stability analysis was based on the modified Floquet exponents approach. We found the stable solution at frequencies of geometrical resonances which corresponded to zero-field steps in IV-characteristics. We investigated stability of the solution of dynamic equations for two long junctions which interacted inductively with each other. We proved the existence of stable phase-locking of all long junctions at zero-field steps. The developed model can be used for the explanation of experiments on coherent emission of intrinsic Josephson junctions.

Consider the Fukaya category associated to a Lefschetz fibration. It turns out that the Floer cohomology of the monodromy around ∞ gives rise to natural transformations from the Serre functor to the identity functor, in that category. We pay particular attention to the implications of that idea for Lefschetz pencils.

We investigate the iron-based superconductor Ba(Fe 1−x Co x ) 2As 2 (Ba-122) regarding its superconducting properties and possible applications. Therefore, Ba-122 thin films are used as base electrode to prepare different kinds of hybrid Josephson junctions with a counter electrode of the conventional superconductor Pb. Additionally, we use both c-axis and a b-plane transport geometries and different kinds of barriers like interface-engineered surfaces, sputtered titanium oxide and gold layers. Temperature dependent I– V characteristics as well as magnetic field dependence and microwave response of the junctions are shown. The examined I– V characteristics and I c R n– T behaviours of each junction type are compared and described according to the electrical behaviour of the respective normal conducting or insulating barrier. While the I c R n product of the interface-engineered barrier junction was 12 μV and the planar junction with Au barrier showed 18 μV, we could increase the I c R n to 90 μV for planar TiO x barrier junctions.

IV-characteristics of shunted microbridges made of Tl2Ba2CaCu2O8 (TBCCO) were measured. The TBCCO films were grown epitaxially on 20° misaligned LaAlO3 substrates and then covered by the gold shunting layer. Each of the microbridges consisted of about 360 shunted intrinsic Josephson junctions. Self-induced resonant particularities with a main period of about 17 mV were found on IV-curves. We showed that these particularities did not depend on the characteristics of the individual junctions and that they were connected with the geometrical dimensions of the system. The origin of particularities was the interaction of Josephson generation with the standing wave appeared in the system. We modeled this interaction considering radiation of junctions into the transmission line and found that the model described the main resonant structure of IV-characteristics. Strong synchronization of junctions appeared in the vicinity of the first particularity.

In this study the deposition of thin zinc oxide (ZnO) films under atmospheric pressure conditions was investigated. The deposition technique applied was combustion chemical vapour deposition (CCVD), at which a propane–air mixture was combusted in a burner. Dissolved zinc nitrate was used as precursor, which was guided as aerosol droplets by the processing gas flow directly into the reaction zone. Fundamental investigations were performed to form undoped ZnO. The structural properties of the films were analysed in dependence of the substrate temperature during the coating process. The presence of crystalline ZnO structures was proved and differences in film growth and crystallite sizes are revealed. Additionally, the particles generated by the CCVD-flame are characterised. The thin films showed a slight excess of Zn and several states of binding energy could be observed by fitting the core level spectra. Scanning and transmission electron microscopy also indicated ordered structures and additionally different orientations of crystallites were observed.

Recent experiments on synchronized radiation from intrinsic Josephson junctions in high-temperature superconductors showed that the difference of temperatures of the junctions can influence synchronization. We investigated numerically the mechainsm of this influence on the example of two overdamped Josephson junctions loaded by a shunt consisting of the resistance and the inductance. We showed that strong synchronization of radiation was obtained by means of external separate heating/cooling of junctions. Due to the change of critical currents in the process of heating or cooling, the current–voltage (I–V) characteristics of the junctions cross each other and junctions are synchronized by the ac current in the load in the vicinity of this crossing. The maximal tolerant spread of critical currents for this mechanism of synchronization is 15–20% that is twice larger than the maximal tolerant spread for this system without the separate heating. I–V characteristics of two separately heated junctions. Phase locking in this system is impossible without heating for such large spreads of critical currents.

Due to the energy system transformation initiated by the German government, the energy supply structures will be much more decentralized in the future. In the following publication the methodology of a Regional Virtual Power Plant will be described and first results from a field test will be presented.

Using Lefschetz fibrations, we construct nonstandard symplectic structures on cotangent bundles of spheres. These structures are of Liouville type, which means exact and convex at infinity.