A5026575046- Laser-Matter Interactions and Applications
- Corporate Governance and Law
- Advanced Electron Microscopy Techniques and Applications
- Laser-Plasma Interactions and Diagnostics
- Law and Political Science
- Advanced Fiber Laser Technologies
- Spectroscopy and Quantum Chemical Studies
- Cold Atom Physics and Bose-Einstein Condensates
- Diverse Legal and Medical Studies
- Ion-surface interactions and analysis
- Quantum Information and Cryptography
- Public Administration and Political Analysis
- Electron and X-Ray Spectroscopy Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Mass Spectrometry Techniques and Applications
- Advanced X-ray Imaging Techniques
- German Literature and Culture Studies
- Medical and Health Sciences Research
- Terahertz technology and applications
- Near-Field Optical Microscopy
- Laser-induced spectroscopy and plasma
- European and International Law Studies
- Corporate Governance and Management
- Laser Design and Applications
- Advanced Fluorescence Microscopy Techniques
Friedrich-Alexander-Universität Erlangen-Nürnberg
2016-2025
Ludwig-Maximilians-Universität München
2001-2025
Max Planck Institute for the Science of Light
2015-2024
Heidelberg University
2005-2024
Bayer (Germany)
2019-2024
Deutsche Nationalbibliothek
1986-2021
Federal Supreme Court of Switzerland
2019
Carl Zeiss (Germany)
2019
Dr. A. Ramachandran's Diabetes Hospitals
2019
Max Planck Institute of Quantum Optics
2008-2017
We report a source of free electron pulses based on field emission tip irradiated by low-power femtosecond laser. The are shorter than 70 fs and originate from with an area diameter down to 2 nm. Depending the operating regime we observe either photofield or optical up 200 electrons per pulse at repetition rate 1 GHz. This pulsed emitter, triggered oscillator, could serve as efficient for time-resolved interferometry, nanometric imaging synchrotrons.
We describe recent advances in the study of particle acceleration using dielectric near-field structures driven by infrared lasers, which we refer to as Dielectric Laser Accelerators. Implications for high energy physics and other applications are discussed.
A proof-of-principle experiment demonstrating dielectric laser acceleration of nonrelativistic electrons in the vicinity a fused-silica grating is reported. The structure utilized to generate an electromagnetic surface wave that travels synchronously with and efficiently imparts momentum on 28 keV electrons. We observe maximum gradient $25\text{ }\text{ }\mathrm{MeV}/\mathrm{m}$. investigate detail parameter dependencies find excellent agreement numerical simulations. With availability...
Recently two emerging areas of research, attosecond and nanoscale physics, have started to come together. Attosecond physics deals with phenomena occurring when ultrashort laser pulses, duration on the femto- sub-femtosecond time scales, interact atoms, molecules or solids. The laser-induced electron dynamics occurs natively a timescale down few hundred even tens attoseconds, which is comparable optical field. On other hand, second branch involves manipulation engineering mesoscopic systems,...
The fundamental interaction between free electrons and light stands at the base of both classical quantum physics, with applications in free-electron acceleration, radiation sources, electron microscopy. Yet, to this day, all experiments involving interactions are fully explained by describing as a wave, disregarding its nature. Here, we observe statistics effects photons on free-electron-light interactions. We demonstrate passing continuously from Poissonian super-Poissonian up thermal...
We present an experimental and numerical study of electron emission from a sharp tungsten tip triggered by sub-8-fs low-power laser pulses. This process is nonlinear in the electric field, nonlinearity can be tuned via dc voltage applied to tip. Numerical simulations this system show that takes place within less than one optical period exciting pulse, so 8 fs 800 nm pulse capable producing single 1 duration. Furthermore, we find carrier-envelope phase dependence smaller 0.1% for but steeply...
We present energy-resolved measurements of electron emission from sharp metal tips driven with low energy pulses a few-cycle laser oscillator. observe above-threshold photoemission photon order up to 9. At intensity 2*10^11 W/cm^2 suppression the lowest peak occurs, indicating onset strong-field effects. also shifting linearly slope around -1.8eV / (10^12 W/cm^2). attribute magnitude field effects enhancement taking place at tip's surface.
We report the coherent manipulation of internal states neutral atoms in a magnetic microchip trap. Coherence lifetimes exceeding 1 s are observed with at distances 5-130 microm from surface. The coherence lifetime chip trap is independent atom-surface distance within our measurement accuracy and agrees well results similar measurements macroscopic traps. Because absence surface-induced decoherence, miniaturized atomic clock relative stability 10(-13) range can be realized. For applications...
Mechanisms of high-harmonic generation from crystals are described by treating the electric field a laser as quasistatic strong field. Under field, electrons in periodic potentials form dressed states, known Wannier-Stark states. The energy differences between states determine frequencies radiation. radiation yield is determined magnitudes interband and intraband current matrix elements attosecond pulses solids predicted. Ramifications for strong-field physics discussed.
Atomic motion dynamics during structural changes or chemical reactions have been visualized by picosecond and femtosecond pulsed electron beams via ultrafast diffraction microscopy. Imaging the even faster of electrons in atoms, molecules solids requires pulses with sub-femtosecond durations. We demonstrate here all-optical generation trains attosecond free-electron pulses. The concept is based on periodic energy modulation a beam an inelastic interaction ponderomotive potential optical...
One of the astounding consequences quantum mechanics is that it allows detection a target using an incident probe, with only low probability interaction probe and target. This 'quantum weirdness' could be applied in field electron microscopy to generate images beam-sensitive specimens substantially reduced damage specimen. A reduction beam-induced especially great importance if can enable imaging biological atomic resolution. Following recent suggestion interaction-free measurements are...
Nanometre-scale metal tips irradiated by femtosecond laser pulses represent ultrafast electron sources. The combination of the pulse and tip offers possibility extending attosecond science from atomic or molecular gases to surfaces solid nanoemitters. We first review this emerging research field focusing on rescattering at sharp tips. In particular, we investigate carrier–envelope phase effects that reveal emission dynamics. Furthermore, present detailed theory models support interpretation.
We report on a quantitative measurement of the spatial coherence electrons emitted from sharp metal needle tip. investigate in photoemission triggered by near-ultraviolet laser with photon energy 3.1 eV and compare it to dc-field emission. A carbon nanotube is brought into close proximity emitter tip act as an electrostatic biprism. From resulting electron matter wave interference fringes, we deduce upper limit effective source radius both laser-triggered emission mode, which quantifies...
Attosecond science is based on electron dynamics driven by a strong optical electric field and has evolved beyond its original scope in gas-phase atomic molecular physics to solid-state targets. In this review, we discuss nanoscale attosecond laboratory that enabled the first observations of strong-field-driven photoemission recollision at solid surface: laser-triggered metallic nanotips. addition research questions rather fundamental nature, femtosecond sources with outstanding beam...
Dielectric laser acceleration is a versatile scheme to accelerate and control electrons with the help of femtosecond pulses in nanophotonic structures. We demonstrate here generation train electron individual pulse durations as short 270±80 attoseconds (FWHM), measured an indirect fashion, based on two subsequent dielectric interaction regions connected by free-space drift section, all single photonic chip. In first region (the modulator), energy modulation imprinted pulse. During free...
We investigate coherent electron dynamics in graphene, interacting with the electric field waveform of two orthogonally polarized, few-cycle laser pulses. Recently, we demonstrated that linearly polarized driving pulses lead to sub-optical-cycle Landau-Zener quantum path interference by virtue combination intraband motion and interband transition [Higuchi et al., Nature 550, 224 (2017)NATUAS0028-083610.1038/nature23900]. Here introduce a pulsed control beam, pulses, observe ensuing dynamics....
The last two decades experimentally affirmed the quantum nature of free electron wave packets by rapid development transmission microscopes into ultrafast, quantum-coherent systems. So far, all experiments were restricted to bounds enabling one or photon-electron interaction sites. We show coherent coupling between electrons and light in a scanning microscope, at unprecedentedly low, subrelativistic energies down 10.4 keV. These not only afford yet-unexplored from ∼0.5 30 keV providing...