Search results for "BAND"
showing 10 items of 2610 documents
The electronic properties of SrTiO3-δ with oxygen vacancies or substitutions
2021
The authors would like to thank R. Dittmann for useful discussions, T. Kocourek, O. Pacherova, S. Cichon, V. Vetokhina, and P. Babor for their contributions to sample preparation and characterization. The authors (M.T., A.D.) acknowledge support from the Czech Science Foundation (Grant No. 19-09671S), the European Structural and Investment Funds and the Ministry of Education, Youth and Sports of the Czech Republic through Programme “Research, Development and Education” (Project No. SOLID21 CZ.02.1.01/0.0/0.0/16-019/0000760). This study was partly supported by FLAG-ERA JTC project To2Dox (L.R. and E.K.). Calculations have been performed on the LASC Cluster in the Institute of Solid State Phy…
A phytosociological analysis of the Brachypodium rupestre (Host) Roem. & Schult. communities of Sicily.
2018
A phytosociological study on the Brachypodium rupestre grasslands in Sicily is presented. These grasslands form discontinuous secondary stands dynamically linked to the deciduous oak woods, which are widespread within the upper-colline, submontane and lower montane belts (800-1400 m) of the Tyrrhenian side of the northern Sicily and in the Sicani mountains. In the study area B. rupestre grasslands were mainly found in colluvial plains or drainage lines where relatively deep and mesic soils occur. In this paper 42 phytosociological relevés were performed and statistically analysed. Two new associations were described and classified in the alliance Polygalo mediterraneae-Bromion erecti (Brome…
Hong Kong’s EDI bandwagon Derailed or on the right track?
1997
In this paper we explore the adoption of a complex networked technology — that of Electronic Data Interchange (EDI) — in the context of Hong Kong. EDI forms a complex and interorganizational innovation and therefore we suggest a multi-theoretical framework to examine its diffusion. The framework takes into account institutional, industry specific and organizational factors in the study of diffusion processes and thus extends the analysis beyond organizational borders. Using the framework we deliver an account of the EDI diffusion in Hong Kong based on field study data. The study clarifies how simultaneous organizational, industry and environmental factors can be brought to bear to understan…
Testing the X-IFU calibration requirements: an example for quantum efficiency and energy resolution
2018
With its array of 3840 Transition Edge Sensors (TESs) operated at 90 mK, the X-Ray Integral Field Unit (X-IFU) on board the ESA L2 mission Athena will provide spatially resolved high-resolution spectroscopy (2.5 eV FWHM up to 7 keV) over the 0.2 to 12 keV bandpass. The in-flight performance of the X-IFU will be strongly affected by the calibration of the instrument. Uncertainties in the knowledge of the overall system, from the filter transmission to the energy scale, may introduce systematic errors in the data, which could potentially compromise science objectives - notably those involving line characterisation e.g. turbulence velocity measurements - if not properly accounted for. Defining…
Subband image coding using filter banks with non-uniform passband distribution
2002
Subband filter banks with non-uniform passband distribution in frequency domain are studied. Several design examples are presented and compared with conventional uniform bandwidth filter banks. Image coding results show that filter banks with non-uniform bandwidth outperform filter banks with uniform bandwidth, especially in low bit rate coding.
Ćwok, kiep i frajer, czyli postać głupiego męża we francuskiej prozie realistycznej i naturalistycznej
2017
The paper discusses the theme of a stupid husband in three texts of French Realism and Naturalism: a novel by Gustave Flaubert and two short stories by Emile Zola and Guy de Maupassant. The main reference for the analysis is a paper by Stefan Symotiuk who divides the category of “fools” into several subcategories, according to reasons and signs of their stupidity. In agreement with Symotiuk’s thought, Flaubert’s Charles Bovary can be considered as a “blockhead”, dull but always glad with himself; Zola’s Mr Chabre is a “dolt”, heavily thinking and likely to hoax; finally, Maupassant’s Mr Lantin is a “dupe”, easily cheated because unable to see things as they are. All the three characters can…
Floquet engineering with quantum optimal control theory
2023
Abstract Floquet engineering consists in the modification of physical systems by the application of periodic time-dependent perturbations. The search for the shape of the periodic perturbation that best modifies the properties of a system in order to achieve some predefined metastable target behavior can be formulated as an optimal control problem. We discuss several ways to formulate and solve this problem. We present, as examples, some applications in the context of material science, although the methods discussed here are valid for any quantum system (from molecules and nanostructures to extended periodic and non periodic quantum materials). In particular, we show how one can achieve the…
Phonon Driven Floquet Matter.
2018
The effect of electron–phonon coupling in materials can be interpreted as a dressing of the electronic structure by the lattice vibration, leading to vibrational replicas and hybridization of electronic states. In solids, a resonantly excited coherent phonon leads to a periodic oscillation of the atomic lattice in a crystal structure bringing the material into a nonequilibrium electronic configuration. Periodically oscillating quantum systems can be understood in terms of Floquet theory, which has a long tradition in the study of semiclassical light-matter interaction. Here, we show that the concepts of Floquet analysis can be applied to coherent lattice vibrations. This coupling leads to p…
Monitoring Electron-Photon Dressing in WSe 2
2016
Optical pumping of solids creates a non-equilibrium electronic structure where electrons and photons combine to form quasiparticles of dressed electronic states. The resulting shift of electronic levels is known as the optical Stark effect, visible as a red shift in the optical spectrum. Here we show that in a pump-probe setup we can uniquely define a non-equilibrium quasiparticle bandstructure that can be directly measurable with photoelectron spectroscopy. The dynamical photon-dressing (and undressing) of the many-body electronic states can be monitored by pump-probe time and angular resolved photoelectron spectroscopy (tr-ARPES) as the photon-dressed bandstructure evolves in time dependi…
Creating stable Floquet–Weyl semimetals by laser-driving of 3D Dirac materials
2017
Nature Communications 8, 13940 (2017). doi:10.1038/ncomms13940