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Related papers: Femtosecond Laser Processing of Germanium: An Ab I…

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To facilitate quantum simulation of open quantum systems at finite temperatures, an important ingredient is to achieve thermalization on a given time-scale. We consider a Rydberg aggregate (an arrangement of Rydberg atoms that interact via…

Quantum Physics · Physics 2018-10-17 C. D. B. Bentley , A. Eisfeld

Much of our knowledge about dynamics and functionality of molecular systems has been achieved with femtosecond time-resolved spectroscopy. Despite extensive technical developments over the past decades, some classes of systems have eluded…

Chemical Physics · Physics 2020-03-25 Bernhard Thaler , Miriam Meyer , Pascal Heim , Markus Koch

Self-compression of multi-millijoule femtosecond laser pulses and dramatic increase of the peak intensity are found in pressurized helium and neon within a range of intensity in which the ionization modification of the material parameters…

Optics · Physics 2015-05-13 I. G. Koprinkov , M. D. Todorov , M. E. Todorova , T. P. Todorov

We investigate the periodic structure formation upon intense femtosecond pulsed irradiation of chrome steel (100Cr6) for linearly polarised laser beams. The underlying physical mechanism of the laser induced periodic structures is explored,…

The complex interaction dynamics of intense femtosecond (fs) pulses and their picosecond (ps)-long leading edge with nanostructured solids occur at both the nanometer and the femtosecond scales, making them extremely difficult to measure…

Plasma Physics · Physics 2024-03-19 Ankit Dulat , Sagar Dam , Sk Rakeeb , Amit D. Lad , Yash M. Ved , G. Ravindra Kumar

Laser excitation has emerged as a means to expose hidden states of matter and promote phase transitions on demand. Such laser induced transformations are often rendered possible owing to the delivery of spatially and/or temporally…

We demonstrate how the shape of femtosecond laser pulses can be tailored in order to obtain maximal ionization of atoms or molecules. For that purpose, we have overlayed a direct-optimization scheme on top of a fully unconstrained…

Computational Physics · Physics 2015-05-13 A. Castro , E. Rasanen , A. Rubio , E. K. U. Gross

This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1]…

Lasers are becoming a more and more important tool in cutting and shaping materials. Improving precision and effectivity is an ongoing demand in science and industry. One possibility are double pulses. Here we study laser ablation of…

Materials Science · Physics 2015-06-19 Johannes Roth , Armin Krauß , Jan Lotze , Hans-Rainer Trebin

The mechanism of ablation of solids by intense femtosecond laser pulses is described in an explicit analytical form. It is shown that at high intensities when the ionization of the target material is complete before the end of the pulse,…

Optics · Physics 2009-11-07 E. G. Gamaly , A. V. Rode , V. T. Tikhonchuk , B. Luther-Davies

A femtosecond mode-locked laser is used for the first time as a broadband infrared source for high resolution Fourier transform absorption spectroscopy. Demontration is made with a Cr^4+:YAG laser. The entire nu_1+nu_3 vibration-rotation…

This chapter aims at identifying what is specific to femtosecond laser ablation. It reviews the essential basic processes which contribute to femtosecond laser ablation of various materials : energy absorption by the material's electrons,…

Materials Science · Physics 2007-05-23 Guillaume Petite

The complex physics of the interaction between short pulse high intensity lasers and solids is so far hardly accessible by experiments. As a result of missing experimental capabilities to probe the complex electron dynamics and competing…

We analyze the dynamics of atom-laser interactions for atoms having multiple, closely spaced, excited-state hyperfine manifolds. The system is treated fully quantum mechanically, including the atom's center-of-mass degree of freedom, and…

Atomic Physics · Physics 2009-11-11 Josh W. Dunn , Chris H. Greene

Melting is an everyday phase transition that is determined by thermodynamic parameters like temperature and pressure. In contrast, ultrafast melting is governed by the microscopic response to a rapid energy input and, thus, can reveal the…

A quantum simulator based on ultracold optically trapped atoms for simulating the physics of atoms and molecules in ultrashort intense laser fields is introduced. The slowing down by about 13 orders of magnitude allows to watch in slow…

Atomic Physics · Physics 2017-02-01 Simon Sala , Johann Förster , Alejandro Saenz

Understanding excited carrier dynamics in semiconductors is crucial for the development of photovoltaics and efficient photonic devices. However, overlapping spectral features in optical/NIR pump-probe spectroscopy often render assignments…

Formation of high spatial frequency laser induced periodic surface structures (HSFL) in germanium by femtosecond mid-IR pulses with wavelengths between $\lambda=2.0$ and $3.6 \; \mathrm{\mu m}$ was studied with varying angle of incidence…

The pursuit of high optical depth and long coherence time in atomic ensembles faces a fundamental thermodynamic constraint: heating enhances light-atom coupling via increased density but degrades coherence through thermal broadening, while…

Atomic Physics · Physics 2025-05-06 Changhao Cheng , Jinxian Guo

We introduce a method of molecular dynamics in shape space aimed at metal clusters. The ionic degrees of freedom are described via a dynamically deformable jellium with inertia parameters derived from an incompressible, irrotational flow.…

Condensed Matter · Physics 2016-09-28 Constantine Yannouleas , Uzi Landman