Zobrazeno 1 - 10
of 88
pro vyhledávání: '"Ulf Saalmann"'
Publikováno v:
Physical Review Research, Vol 5, Iss 1, p L012003 (2023)
Preservation of coherence is a fundamental, yet subtle, phenomenon in open systems. We uncover its relation to symmetries respected by the system Hamiltonian and its coupling to the environment. We discriminate between local and global classes of dec
Externí odkaz:
https://doaj.org/article/74b7374248e34a06a889c0260455db32
Publikováno v:
Physical Review Research, Vol 4, Iss 2, p L022014 (2022)
We identify and describe how intense short light pulses couple to massless Dirac fermions in two-dimensional systems. The ensuing excitation dynamics exhibits unusual scaling with the wavelength of the light due the linear dispersion of the band stru
Externí odkaz:
https://doaj.org/article/63c4982f7a1845f489d6d3aae4506129
Publikováno v:
New Journal of Physics, Vol 17, Iss 7, p 073005 (2015)
For ultrashort VUV pulses with a pulse length comparable to the orbital time of the bound electrons they couple to, we propose a simplified envelope Hamiltonian. It is based on the Kramers–Henneberger representation in connection with a Floquet exp
Externí odkaz:
https://doaj.org/article/2ecdf51258ef41af8fd65c7d8598963e
Autor:
Ulf Saalmann, Jan Michael Rost
Publikováno v:
Faraday Discussions. 237:368-380
Excitation in the valley domains of graphene, around K (warm colors) and K′ (cold colors) are induced by vertically-polarized multi-harmonic pulses (here containing ω and 2ω) with a maximum vector potential matching the distance K–K′.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f44bb7051cb8d401050ef676cf3b1c0a
https://doi.org/10.1039/d2fd00017b
https://doi.org/10.1039/d2fd00017b
Publikováno v:
Physical Review A
Backscattering of delocalized electrons has been recently established [Phys. Rev. A 105, L041101 (2022)] as a mechanism to enhance high-order harmonic generation (HHG) in periodic systems with broken translational symmetry. Here we study this effect
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cc7a787b09c6359886df7c30b55ad663
https://doi.org/10.1103/physreva.106.013105
https://doi.org/10.1103/physreva.106.013105
Publikováno v:
Faraday Discussions
We have constructed deep neural networks, which can map fluctuating photo-electron spectra obtained from noisy pulses to spectra from noise-free pulses. The network is trained on spectra from noisy pulses in combination with random Hamilton matrices,
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7445655c4bb9bf24cdd05184395cc501
https://doi.org/10.1039/d0fd00117a
https://doi.org/10.1039/d0fd00117a
Publikováno v:
Physical Review A
It is shown that electron backscattering can enhance high-harmonic generation in periodic systems with broken translational symmetry. Paradigmatically, we derive for a finite chain of atoms the harmonic cutoff due to electrons backscattered from the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::342e4a55eb18a409bb7bb0d994559af1
https://doi.org/10.1103/physreva.105.l041101
https://doi.org/10.1103/physreva.105.l041101
Publikováno v:
Physical Review Research
Preservation of coherence is a fundamental, yet subtle, phenomenon in open systems. We uncover its relation to symmetries respected by the system Hamiltonian and its coupling to the environment. We discriminate between local and global classes of dec
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::497767179d57aaa3802b938534b99851
Autor:
Ulf Saalmann, Jan M. Rost
Publikováno v:
Physical Review Letters
The generation of a streaking spectrogram is based on energy absorption from the streaking laser. Investigating this absorption we show rigorously under which condition the measured time shift is independent of properties of the streaking light. In t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f6d60d4ac148dc25fd54ce1d1c1aa336
http://arxiv.org/abs/2003.06172
http://arxiv.org/abs/2003.06172
Publikováno v:
Journal of Modern Optics
High intensities in laser-matter interaction drive nonlinear processes. Whereas at low frequencies thereby multi-photon absorption and above-threshold ionization emerges, in the case of high frequencies single-photon absorption remains prevailing. Ho
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::999dfc49d5ca8de32fe1660e7d1bb57d
https://doi.org/10.1080/09500340.2016.1271150
https://doi.org/10.1080/09500340.2016.1271150