Results of first operation of the Israeli Electrostatic-Accelerator Tandem Free-Electron Laser (EA-FEL) are reported. This EA-FEL utilizes a 1.4A electron beam obtained from a parallel flow Pierce-type electron gun. The e-beam is transported into a resonator located inside a planar Halbach configuration wiggler, which is at a potential of 1.4MeV with respect to the cathode. A resonator utilizin...

We propose an analytical approach to characterize undulator radiation near resonance, when the presence of the vacuum-pipe considerably affects radiation properties. This is the case of the far-infrared undulator beamline at the Free-electron LASer (FEL) in Hamburg (FLASH), that will be capable of delivering pulses in the TeraHertz (THz) range. This undulator will allow pump-probe experiments w...

Wavelength-division demultiplexers are a fundamental component needed for many proposed integrated photonic systems. By using filter banks based on microring resonators it is possible to create demultiplexers that are two orders of magnitude smaller and achieve better performance than the discrete component demultiplexers currently used. To create a filter bank out of microring resonators the r...

   Self-heating leads to a temperature rise of the laser diode and limits the output power and efficiency due to increased loss and decreased differential gain. To control device self-heating, it is required to design the laser structure with a low optical loss, while the heat flux must spread out of the device efficiently. In this study, a new asymmetric waveguide design is proposed and th...

The nature of trions and their interaction with light has remained a puzzle. composition dispersion polaritons involving provide insights into this Trions excitons in doped two-dimensional (2D) materials are not independent excitations but strongly coupled as result Coulomb interactions. When 2D also inside an optical waveguide, the resulting polariton states coherent superpositions exciton, tr...

We present a practical method for achieving a transformer ratio (R) greater than 2 with any collinear wakefield accelerator i.e. with either plasma or structure based wakefield accelerators. It is known that the transformer ratio cannot generally be greater than 2 for a symmetric drive bunch in a collinear wakefield accelerator. However, using a ramped bunch train (RBT) where a train of n elect...

There is urgent need to develop new acceleration techniques capable of exceeding gigaelectron-volt-per-metre (GeV m(-1)) gradients in order to enable future generations of both light sources and high-energy physics experiments. To address this need, short wavelength accelerators based on wakefields, where an intense relativistic electron beam radiates the demanded fields directly into the accel...

We consider eigenmodes of a ring resonator made of a circular dielectric waveguide. Taking into account the polarization corrections, which are responsible for the interaction of polarization and orbital properties of electromagnetic waves (spin–orbit interaction of photons), results in fine splitting of the levels of scalar approximation. The basic features of this fine structure of the levels...

Label-free photonic biosensors fabricated on silicon-on-insulator (SOI) can provide compact size, high evanescent field strength at the silicon waveguide surface, and volume fabrication potential. However, due to the large thermo optic coefficient of water-based biosamples, the sensors are temperature-sensitive. Consequently, active temperature control is usually used. However, for low cost app...

The design and measured results of a single-substrate transceiver module suitable for 76–77-GHz pulsed-Doppler radar applications are presented. Emphasis on ease of manufacture and cost reduction of commercial millimeter-wave systems is employed throughout as a design parameter. The importance of using predictive modeling techniques in understanding the robustness of the circuit design is stres...