Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Bieniasz, K." wg kryterium: Autor


Wyświetlanie 1-4 z 4
Tytuł:
Quantum versus Classical Polarons in a Ferromagnetic $CuO_3$-Like Chain
Autorzy:
Bieniasz, K.
Oleś, A.
Powiązania:
https://bibliotekanauki.pl/articles/1374771.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.10.Di
75.10.Pq
75.50.Dd
79.60.-i
Opis:
We present an exact solution for an itinerant hole added into the oxygen orbitals of a $CuO_{3}$-like ferromagnetic chain. Using the Green function method, the quantum polarons obtained for the Heisenberg SU(2) interaction between localized Cu spins are compared with the polarons in the Ising chain. We find that magnons with large energy are favorable towards quasiparticle existence, even in the case of relatively modest electron-magnon coupling. We observe two quasiparticle states with dispersion ~2t each, which emerge from the incoherent continuum when the exchange coupling J increases. Quantum fluctuations in the spin system modify the incoherent part of the spectrum and change the spectral function qualitatively, beyond the bands derived from the perturbation theory.
Źródło:
Acta Physica Polonica A; 2014, 126, 4a; A-80-A-83
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polaron States in a CuO Chain
Autorzy:
Bieniasz, K.
Oleś, A.
Powiązania:
https://bibliotekanauki.pl/articles/1385209.pdf
Data publikacji:
2015-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.10.Di
75.10.Pq
75.50.Ee
Opis:
We introduce a one-dimensional model for a CuO chain, with holes and S=1/2 spins localized in $3d_{x²-y²}$ orbitals, and p_σ oxygen orbitals without holes in the ground state. We consider a single hole doped at an oxygen site and study its propagation by spin-flip processes. We develop the Green function method and treat the hole-spin coupling in the self-consistent Born approximation, similar to that successfully used to study polarons in the regular t-J model. We present an analytical solution of the problem and investigate whether the numerical integration is a good approximation to this solution.
Źródło:
Acta Physica Polonica A; 2015, 127, 2; 269-271
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Green Function Variational Approximation: Significance of Physical Constraints
Autorzy:
Bieniasz, K.
Berciu, M.
Oleś, A.
Powiązania:
https://bibliotekanauki.pl/articles/1398655.pdf
Data publikacji:
2016-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.25.Dk
03.65.Ud
75.10.Lp
79.60.-i
Opis:
We present a calculation of the spectral properties of a single charge doped at a Cu(3d) site of the Cu-F plane in KCuF₃. The problem is treated by generating the equations of motion for the Green function by means of subsequent Dyson expansions and solving the resulting set of equations. This method, dubbed the variational approximation, is both very dependable and flexible, since it is a systematic expansion with precise control over elementary physical processes. It allows for deep insight into the underlying physics of polaron formation as well as for inclusion of many physical constraints, such as excluding crossing diagrams and double occupation constraint, which are not included in the self-consistent Born approximation. Here we examine the role and importance of such constraints by analyzing various spectral functions obtained in second order variational approximation.
Źródło:
Acta Physica Polonica A; 2016, 130, 2; 659-663
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mineral composition of fruits and leaves of San Andreas® everbearing strawberry in soilless cultivation
Autorzy:
Gondek, K.
Mierzwa-Hersztek, M.
Kopec, M.
Zaleski, T.
Bogdal, S.
Bieniasz, M.
Blaszczyk, J.
Kaczmarczyk, E.
Kowalczyk, B.
Knaga, J.
Nawrocki, J.
Pniak, M.
Jarosz, R.
Powiązania:
https://bibliotekanauki.pl/articles/1192501.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Warmińsko-Mazurski w Olsztynie / Polskie Towarzystwo Magnezologiczne im. Prof. Juliana Aleksandrowicza
Tematy:
mineral composition
everbearing strawberry
soilless cultivation
Opis:
Technological progress in the cultivation of horticultural and fruit plants makes the use of soil becoming less and less important. Growing plants in soilless substrates is becoming more and more common. The aim of the study was to determine the variability of the mineral composition of fruits and leaves of everbearing strawberry of the San Andreas® variety in soilless cultivation. Research was carried out at the experimental plantation of Polski Instytut Truskawki Sp. z o.o. (geographical coordinates: 50°02′11″N and 19°81′19″E). The cultivation of everbearing strawberry of the San Andreas® variety was carried out in a gutter system under covers in coconut substrate. The stability of the chemical composition of strawberry leaves and fruits depends on fertilisation, weather factors, and the quality of water used for fertigation. Despite maintaining the content of nutrient in the rhizosphere at the level recommended for organic substrates, low potassium and calcium content and high magnesium content in strawberry leaves were determined. Among the macroelements analysed in strawberry leaves, the lowest variation coefficient values were found for nitrogen, magnesium and calcium, and in fruits – for nitrogen, phosphorus, and magnesium. The highest variation coefficients were obtained for phosphorus and sodium in strawberry leaves, and for sulphur and sodium in strawberry fruits. Variation coefficient values of copper, zinc, and manganese content in leaves were similar. The content of iron in leaves and zinc in fruits was characterised by the lowest variation coefficients during the growing period.
Źródło:
Journal of Elementology; 2020, 25, 4; 1333-1347
1644-2296
Pojawia się w:
Journal of Elementology
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies