English
Related papers

Related papers: Femtosecond time-resolved dynamical Franz-Keldysh …

200 papers

The dynamical Franz-Keldysh effect, indicative of the transient light-matter interaction regime between quantum and classical realms, is widely recognized as an essential signature in wide bandgap condensed matter systems such as…

Mesoscale and Nanoscale Physics · Physics 2024-07-09 Youngjae Kim

In (100)-oriented GaAs illuminated at normal incidence by a laser and its second harmonic, interference between one- and two-photon absorption results in ballistic current injection, but not modulation of the overall carrier injection rate.…

Other Condensed Matter · Physics 2011-03-30 J. K. Wahlstrand , H. Zhang , S. B. Choi , S. Kannan , D. S. Dessau , J. E. Sipe , S. T. Cundiff

We investigate non-equilibrium electron dynamics in crystalline ZnO induced by ultrashort, relatively intense, infrared laser pulses. Our focus is on understanding the mechanism that facilitates efficient conduction band population in ZnO…

Materials Science · Physics 2025-03-21 Xiao Chen , Thomas Lettau , Ulf Peschel , Nicolas Tancogne-Dejean , Silvana Botti

Real-time time-dependent density functional theory, in conjunction with the Ehrenfest molecular dynamics scheme, is becoming a popular methodology to investigate ultrafast phenomena on the nanoscale. Thanks to recent developments, it is…

Materials Science · Physics 2020-08-18 Jannis Krumland , Ana M. Valencia , Stefano Pittalis , Carlo A. Rozzi , Caterina Cocchi

The advent of high-average-power, ultrafast ytterbium-based lasers allows us to generate laser filaments at repetition rates ranging from 10s of kHz up to 100s of kHz. At such high repetition rates, the inter-pulse time lies below the time…

Optics · Physics 2025-06-04 Robin Löscher , Malte C. Schroeder , Alan Omar , Clara J. Saraceno

We studied time-dependent features of high-frequency fluorescent radiation from a two-level quantum system with broken inversion spatial symmetry. The system in question was modelled after a one-electron two-level asymmetric polar…

Quantum Physics · Physics 2024-12-17 Andrey V. Soldatov

The Dynamical Franz-Keldysh Effect is exposed by exploring near-bandgap absorption in the presence of intense THz electric fields. It bridges the gap between the DC Franz- Keldysh effect and multi-photon absorption and competes with the THz…

Mesoscale and Nanoscale Physics · Physics 2019-08-17 K. B. Nordstrom , K. Johnsen , S. J. Allen , A. -P. Jauho , B. Birnir , J. Kono , T. Noda , H. Akiyama , H. Sakaki

We introduce a wide-field magneto-optical microscope to probe magnetization dynamics with femtosecond temporal and sub-micrometer spatial resolution. We carefully calibrate the non-linear dependency between the magnetization of the sample…

Time-resolved measurements of quantum dynamics are based on the availability of controlled events (e.g. pump and probe pulses) that are shorter in duration than the typical evolution time scale of the dynamical processes to be observed.…

Similar to the optical diffraction of light passing through a material grating, the Kapitza-Dirac effect occurs when an electron is diffracted by a standing light wave. In its original description the effect is time-independent. In the…

Time-resolved studies have so far relied on rapidly triggering a photo-induced dynamic in chemical or biological ions or molecules and subsequently probing them with a beam of fast moving photons or electrons that crosses the studied…

Chemical Physics · Physics 2021-03-19 Hazem Daoud , R. J. Dwayne Miller

We present a theoretical study of the electronic transport through a many-level quantum dot driven by time-dependent signals applied at the contacts to the leads. If the barriers oscillate out of phase the system operates like a turnstile…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Valeriu Moldoveanu , Vidar Gudmundsson , Andrei Manolescu

Studying time-dependent behavior in lasers is analytically difficult due to the saturating non-linearity inherent in the Maxwell-Bloch equations and numerically demanding because of the computational resources needed to discretize both time…

Optics · Physics 2015-12-23 O. Malik , K. G. Makris , H. E. Türeci

We introduce a model description of femtosecond laser induced desorption at surfaces. The substrate part of the system is taken into account as a (possibly semi-infinite) linear chain. Here, being especially interested in the early stages…

Mesoscale and Nanoscale Physics · Physics 2016-05-25 Emil Boström , Anders Mikkelsen , Claudio Verdozzi

Quantum effects of plasmonic phenomena have been explored through ab-initio studies, but only for exceedingly small metallic nanostructures, leaving most experimentally relevant structures too large to handle. We propose instead an…

Mesoscale and Nanoscale Physics · Physics 2015-09-24 Wei Yan , Martijn Wubs , N. Asger Mortensen

We present an experimental study of the effects of temporal modulation of the pump intensity on a random laser. The nanosecond pump pulses exhibit rapid intensity fluctuations which differ from pulse to pulse. Specific temporal profiles of…

Optics · Physics 2019-01-10 Stefan Bittner , Sebastian Knitter , Seng Fatt Liew , Hui Cao

The time-dependent Dirac equation is solved using the three-dimensional Finite Difference-Time Domain (FDTD) method. The dynamics of the electron wave packet in a vector potential is studied in the arrangements associated with the…

Quantum Physics · Physics 2009-09-15 Neven Simicevic

Ultrahigh peak power femtosecond laser pulses create extreme states of matter that are currently being probed with great interest. Plasma optics have been proposed for shaping and amplifying high-power pulses, but they are subject to huge…

This paper gives an introduction to the Keldysh formalism, with emphasis on its usefulness in time-dependent density functional theory. In the first part we introduce the Keldysh contour and the one-particle Green function defined on this…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Robert van Leeuwen , Nils Erik Dahlen , Gianluca Stefanucci , Carl-Olof Almbladh , Ulf von Barth

Using time-dependent density functional theory, applied to valence electrons, coupled non-adiabatically to molecular dynamics of the ions, we study the induced dynamics of ethylene subjected to the laser field. We demonstrate the reliable…

Atomic and Molecular Clusters · Physics 2009-03-31 Z. P. Wang , P. M. Dinh , P. -G. Reinhard , E. Suraud , F. S. Zhang