Autor: Zakrzewski, D. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Quantum Bright Soliton in a Disorder Potential
Autorzy:: Sacha, K.
Delande, D.
Zakrzewski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1585122.pdf
Data publikacji:: 2009-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 03.75.Lm
72.15.Rn
05.30.Jp
Opis:: At very low temperature, a quasi-one-dimensional ensemble of atoms with attractive interactions tend to form a bright soliton. When exposed to a sufficiently weak external potential, the shape of the soliton is not modified, but its external motion is affected. We develop in detail the Bogoliubov approach for the problem, treating, in a non-perturbative way, the motion of the center of mass of the soliton. Quantization of this motion allows us to discuss its long time properties. In particular, in the presence of a disordered potential, the quantum motion of the center of mass of a bright soliton may exhibit Anderson localization, on a localization length which may be much larger than the soliton size and could be observed experimentally.
Źródło:: Acta Physica Polonica A; 2009, 116, 5; 772-778
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Chaos Assisted Tunneling and Nonspreading Wave Packets
Autorzy:: Zakrzewski, J.
Delande, D.
Buchleitner, A.
Powiązania:: https://bibliotekanauki.pl/articles/1968540.pdf
Data publikacji:: 1998-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 05.45.+b
32.80.Rm
42.50.Hz
Opis:: Consider an initial state lying on a primary resonance island. The state may tunnel into the chaotic sea surrounding it and further escape to infinity via chaotic diffusion. Properties of transport in such a situation are studied on an exemplary system - the hydrogen atom driven by microwaves. We show that the combination of tunneling followed by chaotic diffusion leads to peculiar large scale fluctuations of the AC Stark shift and ionization rates. An appropriate random matrix model describes accurately these statistical properties.
Źródło:: Acta Physica Polonica A; 1998, 93, 1; 179-186
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Many-Body Localization for Randomly Interacting Bosons
Autorzy:: Sierant, P.
Delande, D.
Zakrzewski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1033315.pdf
Data publikacji:: 2017-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: many-body localization
Bose-Hubbard model
disorder in many-body physics
mobility edge
Opis:: We study many-body localization in a one dimensional optical lattice filled with bosons. The interaction between bosons is assumed to be random, which can be realized for atoms close to a microchip exposed to a spatially fluctuating magnetic field. Close to a Feshbach resonance, such controlled fluctuations can be transfered to the interaction strength. We show that the system reveals an inverted mobility edge, with mobile particles at the lower edge of the spectrum. A statistical analysis of level spacings allows us to characterize the transition between localized and excited states. The existence of the mobility edge is confirmed in large systems, by time dependent numerical simulations using tDMRG. A simple analytical model predicts the long time behavior of the system.
Źródło:: Acta Physica Polonica A; 2017, 132, 6; 1707-1712
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 4.

Tytuł:: Extracting Information from Non Adiabatic Dynamics: Excited Symmetric States of the Bose-Hubbard Model
Autorzy:: Łącki, M.
Delande, D.
Zakrzewski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1492502.pdf
Data publikacji:: 2011-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 67.85.Hj
03.75.Kk
03.75.Lm
Opis:: Using Fourier transform on a time series generated by unitary evolution, we extract many-body eigenstates of the Bose-Hubbard model corresponding to low energy excitations, which are generated when the insulator-superfluid phase transition is realised in a typical experiment. The analysis is conducted in a symmetric external potential both without and with a disorder. A simple classification of excitations in the absence disorder is provided. The evolution is performed assuming the presence of the parity symmetry in the system rendering many-body quantum states either symmetric or antisymmetric. Using symmetry-breaking technique, those states are decomposed into elementary one-particle processes.
Źródło:: Acta Physica Polonica A; 2011, 120, 6A; A-178-A-184
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 5.

Tytuł:: Spatial Correlations of Donor Charges in MBE CdTe
Autorzy:: Suski, T.
Wiśniewski, P.
Litwin-Staszewska, E.
Wasik, D.
Przybytek, J.
Baj, M.
Karczewski, G.
Wojtowicz, T.
Zakrzewski, A.
Kossut, J.
Powiązania:: https://bibliotekanauki.pl/articles/1934021.pdf
Data publikacji:: 1995-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Ey
71.55.Gs
Opis:: We present experimental evidence that at high pressures indium donors in CdTe localize electrons in spatially correlated manner. We have studied Hall mobility, μ$\text{}_{H}$, as a function of electron concentration, n$\text{}_{H}$, at T=77 K. Changes of n$\text{}_{H}$ have been achieved by two methods. High pressure freeze-out of electrons onto localized states of In-donors leads to the mobility enhancement with respect to the situation when n$\text{}_{H}$ has been modified by means of a subsequent annealing of the sample. As a result, depending on the degree of spatial correlations in the impurity charges arrangement, different values of μ$\text{}_{H}$ correspond to the same value of n$\text{}_{H}$. The variation of mobility with electron concentration suggests that the localized state of In-donor represents likely negatively charged DX state.
Źródło:: Acta Physica Polonica A; 1995, 88, 5; 929-932
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

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