Informacja

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

Wyszukujesz frazę "KR." wg kryterium: Wszystkie pola


Tytuł:
Electron-Optical Phonon Coupling in Double-Barrier Quantum Well Structure
Autorzy:
Kaczmarek, E.
Powiązania:
https://bibliotekanauki.pl/articles/1932087.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.Gk
63.20.Kr
Opis:
The electron-LO phonon coupling constant for double-barrier quantum well structure was calculated using the Frohlich model of the electron-phonon interaction and assuming coupling of the confined electron with bulk LO phonon mode. Magnitude of the Huang-Rhys factor g and possibility of detecting of phonon replicas in the resonant tunneling current are discussed for GaAs-Al$\text{}_{x}$Ga$\text{}_{1-x}$As and CdTe based structures.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 233-236
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phonon-Assisted Excitation Transfer in Quantum Dot Molecules
Autorzy:
Rozbicki, E.
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047376.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
73.63.Kv
Opis:
We derive a quantum-kinetic description of phonon-assisted Förster transfer between two coupled quantum dots (a quantum dot molecule). We show that the exciton state decays to the ground state of the quantum dot molecule via a combination of the Rabi rotation and exponential decay. For moderately spaced dots this process takes place on a picosecond timescale.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 197-202
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parametric Phonon-Helicon Interaction in Centrosymmetric Crystals with Strain-Dependent Dielectric Constant
Autorzy:
Artemenko, O. L.
Sevruk, B. B.
Powiązania:
https://bibliotekanauki.pl/articles/1945729.pdf
Data publikacji:
1996-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
Opis:
The process of interaction between circularly polarized coherent transverse phonons and slow electrokinetic waves in the centrosymmetric crystal placed in a longitudinal magnetic field and possessing strong strain dependence of the dielectric constant caused by the electrostriction is considered. The cut-off system of equations for the process of nonlinear four-wave interaction in crystal with a quadratic electrostriction corresponding to direct energy conversion from helicon to acoustic wave is derived. The solution is sought for numerically in the vicinity of a synchronism point determined by the intersection of helicon and phonon dispersion curves at different values of semiconductor plasma parameters. The results show the possibility of effective phonon parametric amplification in semiconductor crystal with the electroinduced elastic anisotropy.
Źródło:
Acta Physica Polonica A; 1996, 90, 3; 531-539
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Size Dependent Acoustical Properties of bcc Metal
Autorzy:
Yadav, R. R.
Pandey, D. K.
Powiązania:
https://bibliotekanauki.pl/articles/2043375.pdf
Data publikacji:
2005-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
62.20.Dc
62.65.+k
63.20.Kr
Opis:
The ultrasonic attenuation is evaluated at 300 K along [100], [110], and [111] directions for the characterization of bcc metal Ta. The size of the metal is considered in nanorange. Ultrasonic velocity, Grüneisen parameter and acoustic coupling constant that depend on second and third order elastic constants are calculated for determination of ultrasonic attenuation coefficient. Second and third order elastic constants of the bcc metal Ta at nanoscale at 300 K are also calculated starting with only two basic parameters. For the information about defects at nanoscale, the dislocation drag coefficients are calculated for the metal at different size along [100] orientation. The ultrasonic attenuation increases with the size of material as the size variation of the thermal conductivity and the thermal relaxation time. There is significant increase in the attenuation up to 150 nm.
Źródło:
Acta Physica Polonica A; 2005, 107, 6; 933-946
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Gd$\text{}^{3+}$ Spin-Phonon Interactions in Rare-Earth Fluoride Crystals
Autorzy:
Paradowski, M. L.
Misiak, L. E.
Powiązania:
https://bibliotekanauki.pl/articles/2035540.pdf
Data publikacji:
2002-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
76.30.Kg
Opis:
The X-band EPR study of Gd$\text{}^{3+}$-doped LaF$\text{}_{3}$, La$\text{}_{0.9}$Ce$\text{}_{0.1}$F$\text{}_{3}$, La$\text{}_{0.9}$Nd$\text{}_{0.1}$F$\text{}_{ }$3, LiYF$\text{}_{4}$ and LiY$\text{}_{0.9}$Yb$\text{}_{0.1}$F$\text{}_{4}$ single crystals in the temperature range 4.2-295 K was carried out in order to investigate the Gd$\text{}^{3+}$ spin-phonon interactions. Spin-Hamiltonian parameters are analysed in the light of the superposition model and the rotational invariance theory for phonon-induced contributions to spin-Hamiltonian parameters. The 4f$\text{}^{7}$ electron-phonon interactions can be described by the Debye model. It is suggested, from the rotational invariance mechanism for phonon-induced contributions to spin-Hamiltonian parameters, that the rotational contributions are much smaller than those from the strain. Temperature-induced distortions of the crystal field, as well as these distortions caused by the La$\text{}^{3+}$/Nd$\text{}^{3+}$ and Y$\text{}^{3+}$/Yb$\text{}^{3+}$ substitutions, influence significantly the 4f$\text{}^{7}$ electron-phonon interactions. The coupling constant K$\text{}_{2}$ of 4f$\text{}^{7}$ electrons to the whole phonon spectrum of the crystal lattice is stronger in the LaF$\text{}_{3}$, La$\text{}_{0.9}$Ce$\text{}_{0.1}$F$\text{}_{3}$, La$\text{}_{0.9}$Nd$\text{}_{0.1}$F$\text{}_{3}$ with larger temperature-induced distortion of the Gd$\text{}^{3+}$ site symmetry than in LiYF$\text{}_{4}$, LiY$\text{}_{0.9}$Yb$\text{}_{0.1}$F$\text{}_{4}$. Our results are compared with those for Gd$\text{}^{3+}$-doped RbCdF$\text{}_{3}$ and PbF$\text{}_{2}$ single crystals.
Źródło:
Acta Physica Polonica A; 2002, 102, 3; 373-384
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Collective Encoding of Quantum Information in a Quantum Dot Register
Autorzy:
Grodecka, A.
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2046914.pdf
Data publikacji:
2006-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
63.20.Kr
03.67.Pp
Opis:
We define the collective logical quantum bit as a state on an array of 2, 4, and 8 quantum dots. We show that such an array can be controlled with less phonon-induced pure dephasing than a single dot. We calculate the dephasing accompanying a single-qubit operation on the collective logical qubit by means of perturbative method describing the open system evolution under arbitrary driving.
Źródło:
Acta Physica Polonica A; 2006, 110, 2; 195-200
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hot Phonons in a Biased Two-Dimensional InGaAs Channel
Autorzy:
Aninkevičius, V.
Liberis, J.
Matulionis, A.
Matulionienė, I.
Powiązania:
https://bibliotekanauki.pl/articles/1818476.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
72.20.Ht
Opis:
Experimental dependence of microwave noise temperature on supplied electric power is used to estimate hot-phonon number in a modulation-doped In_{0.52}Al_{0.48}As/In_{0.53}Ga_{0.47}As/In_{0.7} Ga_{0.3}As/In_{0.52}Al_{0.48}As two-dimensional electron gas channel (n_{2D}=2.3×10^{12} cm^{-2}). The nonequilibrium occupancy of the involved longitudinal optical phonon states exceeds the equilibrium one nearly twice at 2 kV/cm electric field. test
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 304-309
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Field Dependence of Phonon-Induced Drag Current of 2D Carriers
Autorzy:
Lehmann, D.
Jasiukiewicz, Cz.
Paszkiewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/1968318.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
73.40.-c
Opis:
The magnetic field dependence of the drag current induced by beams of acoustic phonons is studied in a 2D gas of carriers, formed in a heterostructure. This drag current is related to the velocity of the center of mass of the gas. The elimination of the degrees of freedom related to the relative motion of the carriers leads to a Langevin equation for the center-of-mass position vector. From this equation one can obtain an expression for the induced current density which depends on carrier density-density correlation functions. An explicit formula for the time-integrated current density is derived taking into account all intra and inter Landau level transitions. Corresponding numerical results are in good agreement with the experimental patterns.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 891-894
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phonon-Induced Dephasing of Optically Driven Exciton States in Quantum Dots: Spectral Interpretation
Autorzy:
Machnikowski, P.
Jacak, L.
Powiązania:
https://bibliotekanauki.pl/articles/2044498.pdf
Data publikacji:
2005-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
63.20.Kr
03.65.Yz
Opis:
We discuss phonon-induced perturbation of optically driven coherent dynamics of a confined exciton in a quantum dot in terms of nonlinear spectra of the driving pulse. Damping of pulse-area-dependent Rabi oscillations and phonon-assisted pumping of optically inactive states are analyzed.
Źródło:
Acta Physica Polonica A; 2005, 108, 5; 761-767
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phonon-Induced Dephasing in Quantum Dots - Interpretation in Terms of Information Leakage
Autorzy:
Roszak, K.
Machnikowski, P.
Jacak, L.
Powiązania:
https://bibliotekanauki.pl/articles/2046995.pdf
Data publikacji:
2006-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
03.65.Ta
63.20.Kr
Opis:
We show that the phonon-induced pure dephasing of excitons in quantum dots can be interpreted in terms of information leakage from the carrier subsystem to the lattice environment. We derive a quantitative relation between the coherence of the system, as manifested by the amplitude of the coherent optical polarization, and the amount of available which path information on the system state, quantified by the distinguishability of states.
Źródło:
Acta Physica Polonica A; 2006, 110, 3; 325-330
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phonon Induced Drag of Charge Carriers in Heterostructures in Magnetic Fields: Limit of Weak Fields
Autorzy:
Jasiukiewicz, Cz.
Lehmann, D.
Paszkiewicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/1950859.pdf
Data publikacji:
1996-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
73.40.-c
Opis:
The response of a 2D gas of charge carriers of mobility μ in magnetic field B to pulsed phonon beams is considered. Previously we derived a quantum Langevin equation for the centre-of-mass of the carrier gas, which allows us to calculate the time integrated drag current. This formula is studied in the weak magnetic field limit. When the ratio of the cyclotron frequency ω$\text{}_{c}$ to the frequency ω of phonons is small and μB ≪ 1, the general formula coincides with the corresponding expression obtained in the frame of the Boltzmann equation with the collision integral independent of B.
Źródło:
Acta Physica Polonica A; 1996, 90, 4; 829-832
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Observation of Second-Generation Nonequilibrium Phonons in Highly Photoexcited CdS Microcrystals
Autorzy:
Kurilc̆ik, G.
Strumskis, M.
Jurs̆ėnas, S.
Z̆ukauskas, A.
Powiązania:
https://bibliotekanauki.pl/articles/1952036.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.Kr
78.47.+p
78.55.Et
Opis:
Luminescence kinetics of nonthermalized electron-hole plasma in highly excited CdS microcrystals embedded in glass was studied at T=295 K using two pump pulses technique. The observed carrier kinetics shows additional increase in the effective temperature during the pump pulse as a result of the prepump pulse. The increase is shown to be produced by a fusion of long-lived second-generation nonequilibrium phonons generated by the prepump pulse. The experimental results are in good agreement with a model of hot electron-hole plasma energy relaxation with a build-up of two generations of nonequilibrium phonons.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 875-878
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Complete and Partial Loss of Entanglement Due to a Phonon-Assisted Dephasing Process
Autorzy:
Roszak, K.
Machnikowski, P.
Jacak, L.
Powiązania:
https://bibliotekanauki.pl/articles/2046996.pdf
Data publikacji:
2006-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.67.Lx
03.65.Yz
63.20.Kr
Opis:
We study the evolution of entanglement between two excitons in a double quantum dot system coupled to a super-Ohmic reservoir. As expected entanglement is more fragile than local coherence, but, surprisingly, for a set of pure states disentanglement can be complete in a finite time under conditions that lead to the usual partial pure-dephasing.
Źródło:
Acta Physica Polonica A; 2006, 110, 3; 331-336
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geometry of the $\text{}^4T_{2g}$ Excited State in $Cs_2SiF_6:Mn^{4+}$
Autorzy:
Reisz, A.
Avram, C.
Powiązania:
https://bibliotekanauki.pl/articles/1815472.pdf
Data publikacji:
2007-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.70.Ej
63.20.Kr
63.70.+h
Opis:
The aim of this paper is to calculate the equilibrium displacements of the $\text{}^4T_{2g}$ potential surface minimum from the ground state along the $a_{1g}$ and $e_g$ Jahn-Teller active modes for the octahedral $[MnF_6]^{2-}$ cluster obtained by doping $Mn^{4+}$ ions in $Cs_2SiF_6$ host crystal. The equilibrium displacements in normal and Cartesian coordinates were estimated from force constants of $[MnF_6]^{2-}$ cluster and Huang-Rhys factors associated with the Jahn-Teller stabilization energy. A net equatorial expansion and an axial stretching of the geometry of the $[MnF_6]_{2-}$ cluster in first $\text{}^4T_{2g}$ excited state, as combined effect of the $a_{1g}$ and $e_g$ displacements, were demonstrated.
Źródło:
Acta Physica Polonica A; 2007, 112, 5; 829-833
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Structural and Magnetic Dynamical Properties of Solids. Experimental Approach with Inelastic Neutron Scattering
Autorzy:
Hennion, B.
Powiązania:
https://bibliotekanauki.pl/articles/2011141.pdf
Data publikacji:
1999-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
63.20.-e
63.20.Kr
75.30.Ds
75.40.Gb
74.25.Ha
Opis:
Inelastic neutron scattering on single crystals is a privileged way to obtain valuable information on dynamical properties of solids. The basis of the technique is summarised. Master formulae and experimental examples for lattice dynamics and spin dynamics studies are presented.
Źródło:
Acta Physica Polonica A; 1999, 96, 5; 629-640
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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