A5009855283- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Gyrotron and Vacuum Electronics Research
- Advanced X-ray Imaging Techniques
- Superconducting Materials and Applications
- Terahertz technology and applications
- Atomic and Subatomic Physics Research
- Bacteriophages and microbial interactions
- Laser-Plasma Interactions and Diagnostics
- Experimental and Theoretical Physics Studies
- Radiation Therapy and Dosimetry
- Crystallography and Radiation Phenomena
- Electromagnetic Simulation and Numerical Methods
- Plasma Diagnostics and Applications
- Advanced Surface Polishing Techniques
Savitribai Phule Pune University
1998-2020
Helmholtz-Zentrum Dresden-Rossendorf
2014-2019
Deutsches Elektronen-Synchrotron DESY
2016
National Agency for New Technologies, Energy and Sustainable Economic Development
2001-2005
Abstract Ultrashort flashes of THz light with low photon energies a few meV, but strong electric or magnetic field transients have recently been employed to prepare various fascinating nonequilibrium states in matter. Here we present new class sources based on superradiant enhancement radiation from relativistic electron bunches compact accelerator that believe will revolutionize experiments this field. Our prototype source generates high-field pulses at unprecedented quasi-continuous-wave...
Extreme-ultraviolet to x-ray free-electron lasers (FELs) in operation for scientific applications are up now single-user facilities. While most FELs generate around 100 photon pulses per second, FLASH at DESY can deliver almost two orders of magnitude more this time span due its superconducting accelerator technology. This makes the facility a prime candidate realize next step FELs—dividing electron pulse trains into several FEL lines and delivering users same time. Hence, has been extended...
The THz beamline at FLASH, DESY, provides both tunable (1–300 THz) narrow-bandwidth (∼10%) and broad-bandwidth intense (up to 150 uJ) pulses delivered in 1 MHz bursts naturally synchronized with free-electron laser X-ray pulses. Combination of these pulses, along the auxiliary NIR VIS ultrashort lasers, supports a plethora dynamic investigations physics, material science biology. unique features FLASH accelerator source, however, bring set challenges diagnostics their key parameters: pulse...
The generation of frequency-tunable, narrow-bandwidth and carrier-envelope-phase stable THz pulses with fields in the MV/cm regime that can be appropriately timed to femtosecond X-ray from free-electron-lasers is highest scientific interest. It will enable follow electronic structural dynamics stimulated by (non)linear selective excitations matter on few time Ångstrom length scales. In this article, a scheme based superradiant undulator emission generated just after XFEL proposed. concept...
We review the theory of free-electron laser (FEL) oscillators operating with tapered undulators. have considered case a uniform tapering and introduced parameter which characterizes effect on gain saturation intensity. analyzed FEL dynamics by including pulse propagation effects. further analyze importance as tool to model optical shapes control higher harmonic intensities.
A tapered undulator experiment was carried out at the ELBE far-infrared free electron laser (FEL). The oscillator FEL makes use of a hybrid optical resonator. main motivation to see whether presence dispersive medium in form waveguide resonator has any effect on outcome. saturated power and wavelength shifts have been measured as function both positive well negative field amplitude tapering. In contrast typical high-gain FELs where tapering proves beneficial for output we observed an...
Superconducting radiofrequency (SRF) accelerator technology can provide relativistic electron bunches with quasi-cw repetition rates scaling from the kHz to GHz regime [1, 2, 3, 4]. The SRF ELBE [1] is up now Europe’s only linear (LINAC) that has been operating for more than 10 years as a driver several secondary radiation sources. In past four upgraded eventually also allow bunch compression down sub ps regime. Although recent combined electro-optic and interferometric measurements show not...
The effect of dielectric tapering on the extraction efficiency a Cerenkov Free Electron Laser is investigated. A self consistent dynamical model in terms electron energy and radiation phase developed. From numerical simulations based this it shown that can be increased by factor more than two for moderate tapers layers.
The electron linear accelerators driving modern X-ray free-electron lasers can emit intense, tunable, quasi-monochromatic terahertz (THz) transients with peak electric fields of V Å −1 and magnetic in excess 10 T when a purpose-built, compact, superconducting THz undulator is implemented. New research avenues such as movies THz-driven mode-selective chemistry come into reach by making dual use the ultra-short GeV bunches, possible rather minor extension infrastructure.
We consider hybrid free electron laser devices consisting of Cerenkov and undulator sections. will show that they can in principle be used as segmented also the possibility exploiting for generation nonlinear harmonic coherent power. discuss both oscillator amplifier schemes.
A method to taper the field amplitude in permanent magnet undulators without changing undulator gap is presented. It based on deviations patterns of blocks produced by incorrect orientation magnetization vector. The appropriate arrangement determined solving a set linear equations obtained using values which characterize tapered profile. versatility demonstrated simulating different profile shapes same blocks. shown that profiles required shape and size can be proper specifications. results...