High harmonic spin-orbit angular momentum generation in crystalline solids preserving multiscale dynamical symmetry

Symmetries essentially provide conservation rules in nonlinear light-matter interactions, that facilitate control and understanding of photon conversion processes or electron dynamics. Since anisotropic solids have rich symmetries, they are strong candidate to control both optical micro- and macroscale structures, namely spin (circular polarization) and orbital angular momentum (spiral wavefront), respectively. Here, we show structured high harmonic generation linked to the anisotropic symmetry of a solid. By strategically preserving a dynamical symmetry arising from the spin-orbit interaction of light, we generate multiple orbital angular momentum states in high-order harmonics. The experimental results exhibit the total angular momentum conservation rule of light even in the extreme nonlinear region, which is evidence that the mechanism originates from a dynamical symmetry. Our study provides a deeper understanding of multiscale nonlinear optical phenomena and a general guideline for using electronic structure to control structured light, such as through Floquet engineering

ANALIZA AGREGATNE RAZINE MANIPULIRANJA DOBITI U ZEMLJAMA JUGOISTOČNE EUROPE : Diplomski rad

Učinkovitost poduzeća i tržišta ovisi o kvaliteti financijske informacije, tj. o kvaliteti financijskih izvještaja. Financijski izvještaji moraju odražavati stvarno stanje poslovanja poduzeća, moraju biti istiniti, pravedni, pouzdani i nepristrani. Kada se poduzeća ne pridržavaju toga, onda je riječ o manipuliraju izvještajima. Agencijski problem predstavlja osnovu za objašnjenje zašto se manipuliranje događa. Prema agencijskom problemu, sukob menadžera i vlasnika, odnosno njihovi različiti ciljevi, dovode do toga da menadžeri manipuliraju izvještajima. Kao jedan od najčešćih motiva navode se bonusi menadžerima koji su vezani uz ostvarivanje određene razine dobiti. Postoje brojne vrste, tehnike i načini manipuliranja, a smanjuje ih se, odnosno sprječava, računovodstvenim pravilima i standardima, revizijom, budnošću investitora i sl. Brojna istraživanja su pokazala i kako otkriti manipulaciju ako se dogodi. Jedan od načina su Leuzove mjere manipuliranja koje su se koristile i u ovom radu za testiranje hipoteze postoji li razlika u manipuliranju dobiti među zemljama Jugoistočne Europe. Analiza je izvršena na uzorku poduzeća iz Bosne i Hercegovine, Hrvatske, Crne gore, Srbije i Slovenije. Izračuni su pokazali da postoji manipuliranje, i da postoji razlika među zemljama, te je prihvaćena hipoteza.Business and market efficiency depends on the quality of financial information, i.e. the quality of financial reports. The financial reports must reflect the real financial position and performance, must be true, fair, credible and impartial. When companies do not adhere to it, it's about manipulating reports. The agency problem is the basis for explaining why manipulation is happening. According to the agency problem, the conflict between managers and owners and their different goals, leads managers to manipulate reports. As one of the most common motives, there are bonuses for managers if they achive certain level of profit. There are numerous types, techniques and methods of manipulation, and they are reduced or prevented by accounting rules and standards, auditing, investor attitudes, etc. Numerous studies have also shown how to detect manipulation if it occurs. One of the ways is the Leuze's earnings management measures which were also used in this paper to test the hypothesis of whether there is a difference in earnings manipulation among the countries of South East Europe. The analysis was carried out on a sample of companies from Bosnia and Herzegovina, Croatia, Montenegro, Serbia and Slovenia. Calculations have shown that there is manipulation, and there is a difference in manipulation between countries, so the hypothesis is accepted