5,367 research outputs found
Vrddhirane tvorbe v balto-slovanščini
No full textThe aim of this MA thesis is to gather the potential vr̥ddhi formations in Baltic and Slavic languages, analyze them according to the methods of comparative linguistics and evaluate their plausibility and the diachronic stage in which they were created. The main criterion while searching for possible Bl.-Sl. vr̥ddhi formations is the ablaut of the root, which should either reflect an unexpected full grade or length and acute intonation, while simultaneously acknowledging possible different sources of the Balto-Slavic acute. The material is presented in sections ranging from “certain” to “probably incorrect” in the first part and the common characteristics of the formations identified as vr̥ddhi derivatives in individual diachronic stages (Proto-Indo-European, North-West Indo-European, Northern Indo-European, Balto-Slavic, Baltic and Slavic) are discussed in the second part of the thesis.Namen magistrskega dela je zbrati potencialne vrddhirane tvorbe v baltskih in slovanskih jezikih, jih analizirati po metodah primerjalnega jezikoslovja ter oceniti njihovo verjetnost in diahrono stopnjo, v kateri so nastale. Glavno merilo pri iskanju možnih baltoslovanskih vrddhiranih tvorb je prevoj korena, ki naj bi odražal bodisi nepričakovano polno stopnjo bodisi dolžino in akut, ob upoštevanju različnih možnih virov baltoslovanskega akuta. Gradivo je v prvem delu predstavljeno v sklopih od "gotovih tvorb" do "verjetno napačnih", v drugem delu pa so obravnavane skupne značilnosti vrddhiranih tvorb v posameznih diahronih fazah (praindoevropščina, severozahodna indoevropščina, severna indoevropščina, baltoslovanščina, baltščina in slovanščina)
Blackbody radiation and the Weyl law in disordered media
No full textIn my talk, I will discuss an interesting property of blackbody radation when it propagates through complex media, such as disordered materials. As it turns out, the average time spent by the radiation in such a system–or, equivalently, its average path length–is entirely independent of whether the system is strongly disordered (and therefore opaque) or very weakly disordered (and therefore transparent). This property is linked to the so-called "Weyl law", that was discovered in 1911 by Hermann Weyl and allows one to estimate the density of states of a system just based on its geometrical parameters. After introducing this "path length invariance" [1] and its experimental implementations [2,3], I will show how these insights can be connected to information theory [4] and to the forces of the quantum vacuum [5].
[1] R. Pierrat, P. Ambichl, S. Gigan, A. Haber, R. Carminati, and S. Rotter, PNAS 111, 17765 (2014)
[2] R. Savo, R. Pierrat, U. Najar, R. Carminati, S. Rotter, and S. Gigan, Science 358, 765 (2017)
[3] M. Davy, M. Kühmayer, S. Gigan, and S. Rotter, Communications Physics 4, 85 (2021)
[4] M. Horodynski, D. Bouchet, M. Kühmayer, and S. Rotter, Phys. Rev. Lett. 127, 233201 (2021)
[5] L. M. Rachbauer, D. Bouchet, U. Leonhardt, and S. Rotter (manuscript in preparation
Fisher information in scattering problems and neural networks
No full textIn my talk, I will discuss recent progress in applying the concept of Fisher information to the problem of estimating system parameters in complex scattering environments, such as inside or behind a disordered medium [1,2,3]. We have recently realised that such tools can also be successfully applied to artificial neural networks, in particular to define the performance limit of a network in extracting information from a complex system.
[1] Maximum information states for coherent scattering measurements, D. Bouchet, S. Rotter, and A. P. Mosk, Nature Physics 17, 564 (2021).
[2] Optimal control of coherent light scattering for binary decision problems, D. Bouchet, L. M. Rachbauer, S. Rotter, A. P. Mosk, and E. Bossy, Phys. Rev. Lett. 127, 253902 (2021).
[3] Invariance property of the Fisher information in scattering media, M. Horodynski, D. Bouchet, M. Kühmayer, and S. Rotter, Phys. Rev. Lett. 127, 233201 (2021)
Liquid helium flows around an oscillating cylinder
No full textThe complementary flows of normal viscous liquid helium (He I) and of superfluid helium (He II) around an oscillating obstacle, of rectangular cross-section, have been studied experimentally by using the particle tracking velocimetry technique, with solid deuterium particles. The observed particle behaviour in He II is very similar to that seen in He I. It seems therefore that, without some kind of special forcing acting differently on each superfluid helium component, on length scales which the experiment can access, the oscillating quantum flow mimics the classical one
Fisher Information in Electromagnetism
No full textIn my talk, I will discuss recent progress in applying the concept of classical and
quantum Fisher informa;on to the problem of estimating system parameters in
electromagnetic scattaering and nano-photonics. Specifically, I will demonstrate how Fisher Information can be maximised through wavefront shaping and quantum state engineering [1,2]. Quite interestingly, the density and flux of Fisher information satisfy a fundamental continuity equation – in analogy to the Poynting theorem for the density and flux of energy in a radiation field [3]. This viewpoint allows us to identify Fisher information a physical quantity that propagates through space and that can resonate, diffract, and interfere [4]. Finally, I will also say a few words about how such concepts can be generalised to the flow of Fisher Information through Artificial Neural Networks [5].
[1] Maximum information states for coherent scattaering measurements, D. Bouchet, S. Rotter, and A. P. Mosk, Nature Physics 17, 564 (2021).
[2] How to find optimal quantum states for optical micromanipulation and metrology in complex scattering problems, L. M. Rachbauer, D. Bouchet, U. Leonhardt, and S. Rotter, J. Opt. Soc. Am. B 41, 2122 (2024)
[3] Continuity equation for the flow of Fisher information in wave scattering, J. Hüpfl, F. Russo, L. M. Rachbauer, D. Bouchet, J. Lu, U. Kuhl, and S. Rotter, Nature Physics 20, 1294 (2024)
[4] Controlling the flow of information in optical metrology, M. Weimar, H. Zhou, L. Neubacher, T. A. Grant, J. Hüpfl, K. F. MacDonald, S. Rotter, and N. I. Zheludev, arXiv:2508.13640
[5] Fisher information flow in artificial neural networks, M. Weimar, L. M. Rachbauer, I.
Starshynov, D. Faccio, L. Adilova, D. Bouchet, and S. Rotter, Phys. Rev. X 15, 031072 (2025
Multiple Light Fields at Critical Coupling
No full textI will speak about light fields at the condition of critical coupling, with an emphasis on the design of optical systems, where multiple modes satisfy this condition in parallel. As we have shown in recent collaborations with experimental teams, such systems show unique behaviour, such as degenerate perfect absorption [1], as well as perfect transmission of arbitrary coherent wavefronts even across disordered media [2].
References:
1. Y. Slobodkin, G. Weinberg, H. H ̈orner, K. Pichler, S. Rotter, and O. Katz, Science 377, 995 (2022).
2. M. Horodynski, M. Ku ̈hmayer, C. Ferise, S. Rotter, and M. Davy, Nature 607, 281 (2022)
AMČR - projekt M-201600947
No full textStav: 6Podnět: Uh. Hradiště, p. Rotter, přel. Kab skříně. 158.Označení projektu: 2016_02 - UH - Rotter - N
Non-Hermitian Topology in Lasers and Anti-Lasers
No full textn my presentation, I will first speak about the topological aspects of encircling an exceptional point (EP) in a laser and the corresponding chiral state transfer [1]. Building on the insight that EPs can also be identified in the absorption spectra of anti-lasers [2], I will present experimental results on the chiral and degenerate perfect absorption at an EP [3]. Finally, I will show how not only two modes can be critically coupled, but more than a thousand – leading to a massively degenerate coherent perfect absorber for arbitrary incoming wavefronts [4].
[1] A. Schumer, Y. G. N. Liu, J. Leshin, L. Ding, Y. Alahmadi, A. U. Hassan, H. Nasari, S. Rotter, D. N. Christodoulides, P. LiKamWa, and M. Khajavikhan, Science 375, 884 (2022)
[2] W. R. Sweeney, C. W. Hsu, S. Rotter, and A. D. Stone, Phys. Rev. Lett. 122, 093901 (2019)
[3] S. Soleymani, Q. Zhong, M. Mokim, S. Rotter, R. El-Ganainy, and S. K. Özdemir, Nature Commun. 13, 599 (2022)
[4] Y. Slobodkin, G. Weinberg, H. Hörner, K. Pichler, S. Rotter, and O. Katz, Science 377, 995 (2022
Coherent perfect absorption and transmission in disordered media
No full textIn my talk I will present recent work on the perfect absorption and transmission of waves through interferometric cancellation of backscattering. In the first case [1], we demonstrate how to construct an anti-reflection structure for a disordered medium. Similar to an anti-reflection coating for conventional eye-glasses, this structure leads to perfect transmission across the scattering system by suppressing back-scattering for any incoming wavefront. In the second case [2], we demonstrate how to achieve perfect absorption of radiation for the case that an absorber is embedded inside a disordered medium. More recently, we have extended this concept to design a device that can turn even a weakly absorbing film into a “coherent perfect absorber” by placing a degenerate cavity around it [3]. This special cavity perfectly couples incoming light fields with arbitrary wavefronts into the absorber – even for the case that light is a dynamically varying speckle pattern. Successful experimental implementations have been carried out with the groups of Matthieu Davy, Ulrich Kuhl and Ori Katz.
[1] M. Horodynski, M. Kühmayer, C. Ferise, S. Rotter, and M. Davy, Nature 607, 281 (2022)
[2] K. Pichler, M. Kühmayer, J. Böhm, A. Brandstötter, P. Ambichl, U. Kuhl, and S. Rotter, Nature 567, 351 (2019)
[3] Y. Slobodkin, G. Weinberg, H. Hörner, K. Pichler, S. Rotter, and O. Katz, Science 377, 995 (2022
Coherent perfect absorption and transmission of light
No full textIn my talk I will present two recent works focused on the perfect absorption and transmission of waves through interferometric cancellation of backscattering. In the first case [1], we demonstrate that even a weakly absorbing film can be turned into a “coherent perfect absorber” by building a degenerate cavity around it. This special cavity perfectly couples incoming light fields with arbitrary wavefronts into the absorber – even for the case that light is a dynamically varying speckle pattern. In the second case [2], we demonstrate how to construct an anti-reflection structure for a complex scattering system like a disordered medium. Similar to an anti-reflection coating for conventional eye-glasses, this structure leads to perfect transmission across the scattering system by suppressing back-scattering for any incoming wavefront. If time permits, I will also say a few words about the topological origin of the above effects and how this aspect can be used to engineer thermal radiation [3].
[1] Y. Slobodkin, G. Weinberg, H. Hörner, K. Pichler, S. Rotter, and O. Katz, Science 377, 995 (2022)
[2] M. Horodynski, M. Kühmayer, C. Ferise, S. Rotter, and M. Davy, Nature 607, 281 (2022)
[3] M. S. Ergoktas, A. Kecebas, K. Despotelis, S. Soleymani, G. Bakan, A. Kocabas, A. Principi, S. Rotter, S. K. Özdemir, and C. Kocabas, arXiv:2401.0831
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