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The properties of the electron source define the ultimate limit of the beam quality in linear accelerators like Free Electron Lasers (FEL). The goal is to develop an electron gun delivering beam emittance lower than current state of the art. Such a gun should reduce the cost and size of an X-ray Free Electron Laser (XFEL). In this paper we present two concepts of field emitter cathodes which could potentially produce low emittance beam. The first challenging parameter for such cathode is to emit peak current as high as 5 A. This is the minimum current requirement for the XFEL concept from Paul Scherrer Institut.1 Maximum current of 0.12 A and 0.58 A have been reached respectively with field emitter arrays (FEA) and single needle cathodes. Laser assisted field emission gave encouraging results to reach even higher peak current and to pre-bunch the beam.
Field Emitting Arrays (FEAs) are a promising alternative to the conventional cathodes in different vacuum electronic devices such as traveling wave tubes, electron accelerators and etc. Electrical gating and modulation capabilities, together with the
We demonstrate the fabrication of large-scale arrays of single photon emitters (SPEs) in hexagonal boron nitride (hBN). Bottom-up growth of hBN onto nanoscale arrays of dielectric pillars yields corresponding arrays of hBN emitters at the pillar site
Hydrodynamic optically-field-ionized (HOFI) plasma channels up to 100mm long are investigated. Optical guiding is demonstrated of laser pulses with a peak input intensity of $6times10^{17}$ W cm$^{-2}$ through 100mm long plasma channels with on-axis
Monolayer molybdenum disulfide (MoS$_2$) nanosheets, obtained via chemical vapor deposition onto SiO$_2$/Si substrates, are exploited to fabricate field-effect transistors with n-type conduction, high on/off ratio, steep subthreshold slope and good m
We describe the results of experiments and simulations performed with the aim of extending photoelectron spectroscopy with intense laser pulses to the case of molecular compounds. Dimer frame photoelectron angular distributions generated by double io