1,221 research outputs found
On the spectrum of a Hamiltonian defined on su_q(2) and quantum optical models
Analytical expressions are given for the eigenvalues and eigenvectors of a
Hamiltonian with su_q(2) dynamical symmetry. The relevance of such an operator
in Quantum Optics is discussed. As an application, the ground state energy in
the Dicke model is studied through su_q(2) perturbation theory.Comment: 11 pages, LaTeX, content change
The giant effect of magnetic ordering on a sound velocity in a sigma-Fe55Cr45 alloy
We studied atomic dynamics of sigma-Fe(100-x)Cr(x) (x=45 and 49.5) alloys
using nuclear inelastic scattering of synchrotron radiation. For the
sigma-Fe55Cr45 alloy, the derived reduced iron-partial density of phonon states
reveal a huge difference in the low-energy region between magnetic and
paramagnetic states. The latter implies a ca.36% increase of the sound velocity
in the magnetic phase, which testifies to a magnetically-induced hardening of
the lattice.Comment: 8 pages, 3 figures, 17 reference
Religiosity of personality in the context of developmental psychology
In article problems on a joint of psychology of development and psychologists of religion are considered. Theories of stages of religious personal development are brought and analyzed. Theoretical sources of theory of stages of ontogenesis of religiousness are shown.Π ΡΡΠ°ΡΡΠ΅ ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡΡΡ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ, Π½Π°Ρ
ΠΎΠ΄ΡΡΠΈΠ΅ΡΡ Π½Π° ΡΡΡΠΊΠ΅ ΠΏΡΠΈΡ
ΠΎΠ»ΠΎΠ³ΠΈΠΈ ΡΠ°Π·Π²ΠΈΡΠΈΡ ΠΈ ΠΏΡΠΈΡ
ΠΎΠ»ΠΎΠ³ΠΈ ΡΠ΅Π»ΠΈΠ³ΠΈΠΈ. ΠΡΠΈΠ²ΠΎΠ΄ΡΡΡΡ ΠΈ Π°Π½Π°Π»ΠΈΠ·ΠΈΡΡΡΡΡΡ ΡΠ΅ΠΎΡΠΈΠΈ ΡΡΠ°Π΄ΠΈΠΉ ΡΠ΅Π»ΠΈΠ³ΠΈΠΎΠ·Π½ΠΎΠ³ΠΎ ΡΠ°Π·Π²ΠΈΡΠΈΡ Π»ΠΈΡΠ½ΠΎΡΡΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½Ρ ΡΠ΅ΠΎΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΡΡΠΎΠΊΠΈ ΡΡΠ°Π΄ΠΈΠ°Π»ΡΠ½ΡΡ
ΡΠ΅ΠΎΡΠΈΠΉ ΠΎΠ½ΡΠΎΠ³Π΅Π½Π΅Π·Π° ΡΠ΅Π»ΠΈΠ³ΠΈΠΎΠ·Π½ΠΎΡΡΠΈ. Π₯Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΠ·ΡΠ΅ΡΡΡ Π³Π΅Π½Π΅ΡΠΈΡΠ΅ΡΠΊΠ°Ρ ΡΠΏΠΈΡΡΠ΅ΠΌΠΎΠ»ΠΎΠ³ΠΈΡ ΠΊΠ°ΠΊ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠ°Ρ ΠΎΡΠ½ΠΎΠ²Π° Π²ΡΠ΄Π΅Π»Π΅Π½ΠΈΡ ΡΡΠ°Π΄ΠΈΠΉ
General properties of quantum optical systems in a strong field limit
We investigate the dynamics of an arbitrary atomic system (n-level atoms or many n-level atoms) interacting with a resonant quantized mode of an em field. If the initial field state is a coherent state with a large photon number then the system dynamics possesses some general features, independently of the particular structure of the atomic system. Namely, trapping states, factorization of the wave function, collapses and revivals of the atomic energy oscillations are discussed
Supersymmetric oscillator in optics
We show that the supersymmetric structure (in the sense of supersymmetric quantum mechanics) appears in Helmholtz optics describing light propagation in waveguides. For the case of elliptical waveguides, with the accuracy of paraxial approximation it admits a simple physical interpretation. The supersymmetry connects light beams of different colors. The difference in light frequencies for the supersymmetric beams is determined by the transverse gradient of the refractive index. These beams have the save wavelength in the propagation direction and can form a stable interference pattern
Slightly anharmonic systems in quantum optics
We consider an arbitrary atomic system (n-level atom or many such atoms) interacting with a strong resonant quantum field. The approximate evolution operator for a quantum field case can be produced from the atomic evolution operator in an external classical field by a 'quantization prescription', passing the operator arguments to Wigner D-functions. Many important phenomena arising from the quantum nature of the field can be described by such a way
Measurement of synchrotron-radiation-excited Kossel patterns
Kossel line patterns contain information on the crystalline structure, such as the
magnitude and the phase of Bragg reflections. For technical reasons, most of
these patterns are obtained using electron beam excitation, which leads to
surface sensitivity that limits the spatial extent of the structural information. To
obtain the atomic structure in bulk volumes, X-rays should be used as the
excitation radiation. However, there are technical problems, such as the need
for high resolution, low noise, large dynamic range, photon counting, twodimensional
pixel detectors and the small spot size of the exciting beam, which
have prevented the widespread use of Kossel pattern analysis. Here, an
experimental setup is described, which can be used for the measurement of
Kossel patterns in a reasonable time and with high resolution to recover
structural information
Density of Phonon States in Superconducting FeSe as a Function of Temperature and Pressure
The temperature and pressure dependence of the partial density of phonon
states of iron atoms in superconducting Fe1.01Se was studied by 57Fe nuclear
inelastic scattering (NIS). The high energy resolution allows for a detailed
observation of spectral properties. A sharpening of the optical phonon modes
and shift of all spectral features towards higher energies by ~4% with
decreasing temperature from 296 K to 10 K was found. However, no detectable
change at the tetragonal - orthorhombic phase transition around 100 K was
observed. Application of a pressure of 6.7 GPa, connected with an increase of
the superconducting temperature from 8 K to 34 K, results in an increase of the
optical phonon mode energies at 296 K by ~12%, and an even more pronounced
increase for the lowest-lying transversal acoustic mode. Despite these strong
pressure-induced modifications of the phonon-DOS we conclude that the
pronounced increase of Tc in Fe1.01Se with pressure cannot be described in the
framework of classical electron-phonon coupling. This result suggests the
importance of spin fluctuations to the observed superconductivity
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