Rusek M., Orłowski A.
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders confined within a planar metallic waveguide is studied. The disordered dielectric medium is modeled by a system of randomly distributed 2D electric dipoles. An effective theoretical approach based on the method of images is developed. A clear distinction between isolated localized waves (which exist in finite media) and the band of localized waves (which appears only in the limit of the infinite medium) is presented. The Anderson transition emerging in the limit of an infinite medium is observed both in finite size scaling analysis of transmission and in the properties of the spectra of some random matrices. The sound physical interpretation of the obtained results suggests deeper insight into the existing experimental and theoretical work.
Acta Phys. Pol. A vol. 109 (1), 109-119 (2006) [KK, 2/2]
Showing posts with label Marian Rusek. Show all posts
Showing posts with label Marian Rusek. Show all posts
Aug 5, 2005
Emission of Thermally Activated Electrons from Rare Gas Clusters Irradiated with Intense VUV Light Pulses from a Free Electron Laser
Laarmann T, Rusek M, Wabnitz H, Schulz J, de Castro AR, Gürtler P, Laasch W, Möller T
The ionization dynamics of Ar and Xe clusters irradiated with intense vacuum ultraviolet light from a free-electron laser is investigated using photoelectron spectroscopy. Clusters comprising between 70 and 900 atoms were irradiated with femtosecond pulses at 95 nm wavelength (~13 eV photon energy) and a peak intensity of ~4×1012 W/cm2. A broad thermal distribution of emitted electrons from clusters with a maximum kinetic energy up to 30–40 eV is observed. The observation of relatively low-energy photoelectrons is in good agreement with calculations using a time-dependent Thomas-Fermi model and gives experimental evidence of an outer ionization process of the clusters, due to delayed thermoelectronic emission.
Phys Rev Lett. 2005 Aug 5;95(6):063402. Epub 2005 Aug 5
The ionization dynamics of Ar and Xe clusters irradiated with intense vacuum ultraviolet light from a free-electron laser is investigated using photoelectron spectroscopy. Clusters comprising between 70 and 900 atoms were irradiated with femtosecond pulses at 95 nm wavelength (~13 eV photon energy) and a peak intensity of ~4×1012 W/cm2. A broad thermal distribution of emitted electrons from clusters with a maximum kinetic energy up to 30–40 eV is observed. The observation of relatively low-energy photoelectrons is in good agreement with calculations using a time-dependent Thomas-Fermi model and gives experimental evidence of an outer ionization process of the clusters, due to delayed thermoelectronic emission.
Phys Rev Lett. 2005 Aug 5;95(6):063402. Epub 2005 Aug 5
Apr 14, 2005
Different mechanisms of cluster explosion within an unified time-dependent Thomas-Fermi approach: optical and short-wavelength regimes compared
Marian Rusek and Arkadiusz Orlowski
The dynamics of small (55 atoms) argon clusters ionized by an intense femtosecond laser pulse is studied using a time-dependent Thomas-Fermi model. The resulting Bloch-like hydrodynamic equations are solved numerically using the smooth particle hydrodynamics method without the necessity of grid simulations. As follows from recent experiments, absorption of radiation and subsequent ionization of clusters observed in the short-wavelength laser frequency regime (98 nm) differs considerably from that in the optical spectral range (800 nm). Our theoretical approach provides a unified framework for treating these very different frequency regimes and allows for a deeper understanding of the underlying cluster explosion mechanisms. The results of our analysis following from extensive numerical simulations presented in this paper are compared both with experimental findings and with predictions of other theoretical models.
Phys. Rev. A 71, 043202 (2005)
The dynamics of small (55 atoms) argon clusters ionized by an intense femtosecond laser pulse is studied using a time-dependent Thomas-Fermi model. The resulting Bloch-like hydrodynamic equations are solved numerically using the smooth particle hydrodynamics method without the necessity of grid simulations. As follows from recent experiments, absorption of radiation and subsequent ionization of clusters observed in the short-wavelength laser frequency regime (98 nm) differs considerably from that in the optical spectral range (800 nm). Our theoretical approach provides a unified framework for treating these very different frequency regimes and allows for a deeper understanding of the underlying cluster explosion mechanisms. The results of our analysis following from extensive numerical simulations presented in this paper are compared both with experimental findings and with predictions of other theoretical models.
Phys. Rev. A 71, 043202 (2005)
Feb 16, 2005
Free Electrons Generation in the Interaction of Intense Laser Pulses with Atomic Clusters
M. Rusek and A. Orłowski
Interaction of argon clusters with intense laser pulses is studied theoretically. Free electrons energy distribution is studied. Differences between infrared and vacuum ultraviolet frequency regimes are pointed out. Clear physical interpretation of the obtained results is given.
ACTA PHYS. POLONICA A Vol. 107 (2005)
Interaction of argon clusters with intense laser pulses is studied theoretically. Free electrons energy distribution is studied. Differences between infrared and vacuum ultraviolet frequency regimes are pointed out. Clear physical interpretation of the obtained results is given.
ACTA PHYS. POLONICA A Vol. 107 (2005)
May 7, 2004
Dynamics of Argon Clusters in an Intense Laser Pulse: Bloch-Like Hydrodynamic Model
M. Rusek and A. Orłowski
The dynamics of small (≤55 atoms) argon clusters ionized by an intense, infrared, femtosecond laser pulse is studied using a Bloch-like hydrodynamic model. Evolution of both free electrons and ions formed in the cluster explosion process is examined. Oscillations of the electron cloud in a rare-gas atomic cluster are described as a motion of a fluid obeying Bloch-like hydrodynamic equations. Our theoretical approach includes all possible ionization mechanisms: tunnel (or field) ionization both by an external laser field, and by an internal field due to the space-charge distribution inside the cluster, as well as electron-impact (or collisional) ionization. The results of our simulations are compared both with experimental findings and with predictions of other theoretical models.
Acta Phys. Polonica A, Vol. 106 No 1
The dynamics of small (≤55 atoms) argon clusters ionized by an intense, infrared, femtosecond laser pulse is studied using a Bloch-like hydrodynamic model. Evolution of both free electrons and ions formed in the cluster explosion process is examined. Oscillations of the electron cloud in a rare-gas atomic cluster are described as a motion of a fluid obeying Bloch-like hydrodynamic equations. Our theoretical approach includes all possible ionization mechanisms: tunnel (or field) ionization both by an external laser field, and by an internal field due to the space-charge distribution inside the cluster, as well as electron-impact (or collisional) ionization. The results of our simulations are compared both with experimental findings and with predictions of other theoretical models.
Acta Phys. Polonica A, Vol. 106 No 1
Mar 30, 2004
Explosion of Atom Clusters in a Free-Electron Intense Laser Pulse
M. Rusek and A. Orłowski
The explosion of rare-gas atomic clusters induced by short, intense X-ray pulses generated by a free-electron laser is studied. A numerical approach for an explicitly time-dependent description of small to medium size clusters in 3D is developed within the Thomas--Fermi model. Such an approach, though strongly simplified in comparison to fully quantum-mechanical schemes, is nevertheless expected to yield a qualitatively correct description of the electronic and ionic dynamics of these systems, at a much lower computational cost.
Acta Phys. Polonica A, Vol.105 No. 5
The explosion of rare-gas atomic clusters induced by short, intense X-ray pulses generated by a free-electron laser is studied. A numerical approach for an explicitly time-dependent description of small to medium size clusters in 3D is developed within the Thomas--Fermi model. Such an approach, though strongly simplified in comparison to fully quantum-mechanical schemes, is nevertheless expected to yield a qualitatively correct description of the electronic and ionic dynamics of these systems, at a much lower computational cost.
Acta Phys. Polonica A, Vol.105 No. 5
Nov 5, 2003
Optimization of Directional Antennas in Two-Dimensional Artificial Dielectrics
M. Janowicz, M. Rusek and A. Orłowski
We investigate numerically the problem of optimization of directional characteristics of dipole antennas located inside, or in the vicinity of, photonic crystals or more general artificial dielectrics, made of very thin perfectly conducting wires. We concentrate on two-dimensional propagation. Simulated annealing is used to find the distribution of wires which optimizes the directional pattern. It is demonstrated that high directivity can be obtained for systems containing a very small number of elements provided that the size and shape of the unit cell as well as the position of the radiating source with respect to the crystal are optimized. Building up of the radiation pattern is also illustrated with the help of the wave-optical rays.
Acta Physica Polonica A Vol. 105 No. 3
We investigate numerically the problem of optimization of directional characteristics of dipole antennas located inside, or in the vicinity of, photonic crystals or more general artificial dielectrics, made of very thin perfectly conducting wires. We concentrate on two-dimensional propagation. Simulated annealing is used to find the distribution of wires which optimizes the directional pattern. It is demonstrated that high directivity can be obtained for systems containing a very small number of elements provided that the size and shape of the unit cell as well as the position of the radiating source with respect to the crystal are optimized. Building up of the radiation pattern is also illustrated with the help of the wave-optical rays.
Acta Physica Polonica A Vol. 105 No. 3
Jul 17, 2003
Probing Anderson localization of light via decay rate statistics
We have studied the distribution of resonance widths P(Γ) in one-, two-, and three-dimensional multiple light scattering systems. P(Γ) should follow a universal power law P(Γ)∼Γ-1 in the localized regime as confirmed by extensive numerical calculations. This behavior can be interpreted as an unambiguous signature of exponential Anderson localization of light in open systems.
Jul 2, 2003
Cluster explosion in an intense laser pulse
Radiation Physics and Chemistry 68, 273 (2003)
Marian Rusek, Hervé Lagadecb and Thomas Blenskib
This manuscript addresses a hot topic in the field of cluster physics: the explosion of rare-gas atomic clusters induced by short, intense laser pulses. Within the Thomas–Fermi model we have developed an numerical approach for an explicitly time-dependent description of small to medium size clusters in 3D. Such an approach, though strongly simplified in comparison to fully quantum-mechanical schemes, is nevertheless expected to yield a qualitatively correct description of the electronic and ionic dynamics of these systems, at a much lower computational cost.
Marian Rusek, Hervé Lagadecb and Thomas Blenskib
This manuscript addresses a hot topic in the field of cluster physics: the explosion of rare-gas atomic clusters induced by short, intense laser pulses. Within the Thomas–Fermi model we have developed an numerical approach for an explicitly time-dependent description of small to medium size clusters in 3D. Such an approach, though strongly simplified in comparison to fully quantum-mechanical schemes, is nevertheless expected to yield a qualitatively correct description of the electronic and ionic dynamics of these systems, at a much lower computational cost.
May 26, 2000
Cluster explosion in an intense laser pulse: Thomas-Fermi model
Physical Review A 63, 013203 (2001)
Marian Rusek, Herve Lagadec and Thomas Blenski
A refined three-dimensional version of the time-dependent Thomas-Fermi model is used to qualitatively study the explosion of rare-gas atomic clusters in an intense laser field. Clusters as large as 55 atoms are exposed to a strong subpicosecond laser pulse. A stepwise character of the explosion is observed in which atomic shells are expelled sequentially. The role of “hot” electron dynamics in the explosion process is also investigated via initial temperature effects. Contrary to previous opinions it seems that the so-called hydrodynamic explosion scenario is important for most energetic ions coming from the outermost shells only.
Marian Rusek, Herve Lagadec and Thomas Blenski
A refined three-dimensional version of the time-dependent Thomas-Fermi model is used to qualitatively study the explosion of rare-gas atomic clusters in an intense laser field. Clusters as large as 55 atoms are exposed to a strong subpicosecond laser pulse. A stepwise character of the explosion is observed in which atomic shells are expelled sequentially. The role of “hot” electron dynamics in the explosion process is also investigated via initial temperature effects. Contrary to previous opinions it seems that the so-called hydrodynamic explosion scenario is important for most energetic ions coming from the outermost shells only.
Aug 24, 1999
Random Green matrices: From proximity resonances to Anderson localization
Marian Rusek, Jan Mostowski, and Arkadiusz Orłowski
Universal properties of the spectra of certain matrices describing multiple elastic scattering of scalar waves from a collection of randomly distributed point-like objects are discovered. The elements of these matrices are equal to the free-space Green’s function calculated for the differences between positions of any pair of scatterers. A striking physical interpretation within Breit-Wigner’s model of the single scatterer is elaborated. Proximity resonances and Anderson localization are considered as two illustrative examples.
Phys. Rev. A 61, 022704 (2000)
Universal properties of the spectra of certain matrices describing multiple elastic scattering of scalar waves from a collection of randomly distributed point-like objects are discovered. The elements of these matrices are equal to the free-space Green’s function calculated for the differences between positions of any pair of scatterers. A striking physical interpretation within Breit-Wigner’s model of the single scatterer is elaborated. Proximity resonances and Anderson localization are considered as two illustrative examples.
Phys. Rev. A 61, 022704 (2000)
Apr 5, 1999
Bands of localized electromagnetic waves in random collections of dielectric particles
Turkish Journal of Physics 23, 879 (1999)
Marian RUSEK, Arkadiusz ORŁOWSKI
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders is studied. An effective theoretical approach based on the finite size scaling analysis of transmission is developed. The disordered dielectric medium is modeled by a system of randomly distributed 2D electric dipoles. The appearance of the band of localized waves emerging in the limit of an infinite medium is discovered. It suggests deeper insight into existing experimental and theoretical results.
Marian RUSEK, Arkadiusz ORŁOWSKI
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders is studied. An effective theoretical approach based on the finite size scaling analysis of transmission is developed. The disordered dielectric medium is modeled by a system of randomly distributed 2D electric dipoles. The appearance of the band of localized waves emerging in the limit of an infinite medium is discovered. It suggests deeper insight into existing experimental and theoretical results.
Electromagnetic waves in disordered dielectric media: coupled-dipole model
Turkish Journal of Physics 23, 887 (1999)
Arkadiusz ORŁOWSKI and Marian RUSEK
An effective approach to multiple scattering of electromagnetic waves by disordered dielectric media is developed. A self-consistent energy-conserving coupled-dipole model is used. Applications to the Anderson localization of electromagnetic waves are presented. A complete set of Maxwell's equations is used to describe the propagation of waves and the vector character of the electromagnetic field is fully taken into account.
Arkadiusz ORŁOWSKI and Marian RUSEK
An effective approach to multiple scattering of electromagnetic waves by disordered dielectric media is developed. A self-consistent energy-conserving coupled-dipole model is used. Applications to the Anderson localization of electromagnetic waves are presented. A complete set of Maxwell's equations is used to describe the propagation of waves and the vector character of the electromagnetic field is fully taken into account.
Aug 21, 1998
Anderson localization of electromagnetic waves in confined dielectric media
Phys. Rev. E 59, 3655 (1999)
Marian Rusek and Arkadiusz Orłowski
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders confined within a planar metallic waveguide is studied. The disordered dielectric medium is modeled by a system of randomly distributed two-dimensional electric dipoles. An effective theoretical approach based on the method of images is developed. A clear distinction between isolated localized waves (which exist already in finite media) and the band of localized waves (which appears only in the limit of the infinite medium) is presented. The Anderson localization emerging in the limit of an infinite medium is observed both in finite-size scaling analysis of transmission and in the properties of the spectra of some random matrices.
Marian Rusek and Arkadiusz Orłowski
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders confined within a planar metallic waveguide is studied. The disordered dielectric medium is modeled by a system of randomly distributed two-dimensional electric dipoles. An effective theoretical approach based on the method of images is developed. A clear distinction between isolated localized waves (which exist already in finite media) and the band of localized waves (which appears only in the limit of the infinite medium) is presented. The Anderson localization emerging in the limit of an infinite medium is observed both in finite-size scaling analysis of transmission and in the properties of the spectra of some random matrices.
Feb 6, 1997
Band of localized electromagnetic waves in random arrays of dielectric cylinders
Marian Rusek, Arkadiusz Orłowski, and Jan Mostowski
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders is studied. An effective theoretical approach based on analysis of probability distributions, not averages, is developed. The disordered dielectric medium is modeled by a system of randomly distributed two-dimensional electric dipoles. Spectra of certain random matrices are investigated and the appearance of the band of localized waves emerging in the limit of an infinite medium is discovered. It suggests deeper insight into the existing experimental results.
Phys. Rev. E 56, 4892 (1997)
Anderson localization of electromagnetic waves in random arrays of dielectric cylinders is studied. An effective theoretical approach based on analysis of probability distributions, not averages, is developed. The disordered dielectric medium is modeled by a system of randomly distributed two-dimensional electric dipoles. Spectra of certain random matrices are investigated and the appearance of the band of localized waves emerging in the limit of an infinite medium is discovered. It suggests deeper insight into the existing experimental results.
Phys. Rev. E 56, 4892 (1997)
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