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1.
V. M. Vainberg V. A. Gani A. E. Kudryavtsev 《Journal of Experimental and Theoretical Physics》1998,86(2):305-311
The states of a hydrogen atom with principal quantum numbers n⩽3 in a constant uniform magnetic field ℋ are studied. Coefficients in the expansion of the energy of these states in powers
of ℋ2 up to the 75th order are obtained. Series for the energies of the states and the wave functions are summed to values of ℋ
on the order of the atomic magnetic field. A generalization of the moment method upon which these calculations are based can
be used in other cases in which a hydrogen atom is perturbed by a potential with a polynomial dependence on the coordinates.
Zh. éksp. Teor. Fiz. 113, 550–562 (February 1998) 相似文献
2.
The transition energies of the 1s23d-1s2
nf (4⩽n⩽9) transitions and fine structure splittings of 1s2
nf (n⩽9) states for Sc18+ ion are calculated with the full-core plus correlation method. The quantum defect of 1s2
nf series is determined by the single-channel quantum defect theory. The energies of any highly excited states with n⩾10 for this series can be reliably predicted using the quantum defect as function of energy. Three alternative forms of the
dipole oscillator strengths for the 1s23d-1s2
nf (n⩽9) transitions of Sc18+ ion are calculated with the transition energies and wave functions obtained above. Combining the quantum defect theory with
the discrete oscillator strengths, the discrete oscillator strengths for 1s23d-1s2
nf (n > 9) transitions and the oscillator strengths densities corresponding to the bound-free transitions are obtained.
__________
Translated from Chinese Journal of Atomic and Molecular Physics, 2005, 22(4) (in Chinese) 相似文献
3.
Wang Zhi-wen Han Qiu-ju Hu Mu-hong Yang Di Li Jin-ying 《Frontiers of Physics in China》2006,1(1):102-107
The ionization potentials and fine structure splittings of 1s2
nl (l = s, p, and d; n ⩽ 9) states for lithium-like V20+ ion are calculated by using the full-core plus correlation (FCPC) method. The quantum defects of these three Rydberg series
are determined according to the single-channel quantum defect theory (QDT). The energies of any highly excited states with
n ⩾ 10 for these series can be reliably predicted using the quantum defects that are function of energy. The dipole oscillator
strengths for the 1s22s–1s2
np and 1s22p–1s2
nd (n ⩽ 9) transitions of V20+ ion are calculated with the energies and FCPC wave functions obtained above. Combining the QDT with the discrete oscillator
strengths, the discrete oscillator strengths for the transitions from the given initial state to highly excited states (n ⩾ 10) and the oscillator strength density corresponding to the bound-free transitions are obtained.
Translated from Chinese Journal of Atomic and Molecular Physics, 2005(2) (in Chinese) 相似文献
4.
V. S. Egorov E. P. Krasnoperov F. V. Lykov U. Zimmermann G. Solt C. Baines D. Herlach 《Physics of the Solid State》1998,40(3):482-484
We have observed diamagnetic domains (Condon domains) in a beryllium single crystal in magnetic fields H⩽3 T (H∥[0001]) at liquid-helium temperatures. The formation of the domain structure was determined according to magnetic-breakdown
quantum oscillations of the resistance thermoelectric power as well as according to the splitting of the resonance peak of
the free spin precession frequency of muons (μSR). The alternation of a uniform state (with one μSR peak) and a state with
domain structure (with two peaks) is consistent as regards the periodicity with the de Haas-van Alphen effect, the period
is ΔH≅78 Oe, and the range of existence of domains and the difference in their magnetizations are ΔB=4πΔM=B
2−B
1≅30 Oe.
Fiz. Tverd. Tela (St. Petersburg) 40, 524–526 (March 1998) 相似文献
5.
The transition energies, wavelengths and dipole oscillator strengths of 1s22p—1s2
nd (3⩽n⩽9) for Mn22+ ion are calculated. The fine structure splittings of 1s2
nd (n</9) states for this ion are also evaluated. In calculating energy, the higher-order relativistic contribution is estimated
under a hydrogenic approximation. The quantum defect of Rydberg series 1s2
nd is determined according to the quantum defect theory. The results obtained in this paper excellently agree with the experimental
data available in literatures.
Supported by the National Natural Science Foundation of China (Grant No. 10774063) 相似文献
6.
G. M. Maksimova 《Physics of the Solid State》1998,40(10):1607-1610
The mixed state of thin narrow superconducting films with an edge barrier placed in a transverse magnetic field is considered.
The boundaries of the region for the existence of metastable mixed states with an assigned number of vortices N [H
min(N)⩽H⩽H
max(N)] are found. The magnetic-field dependence of the critical field is found for the films. The transition from the Meissner
state to the static mixed state is discussed.
Fiz. Tverd. Tela (St. Petersburg) 40, 1773–1777 (October 1998) 相似文献
7.
E. A. Volkova A. M. Popov O. V. Tikhonova 《Journal of Experimental and Theoretical Physics》2011,113(3):394-406
The dynamics of a model silver atom in the strong radiation field of a Ti:sapphire laser is studied in the Keldysh parameter
regions γ ⩾ 1 and γ ⩽ 1. It is found that in the entire range of Keldysh parameter variations, along with ionization, the
efficient excitation of Rydberg states of the atom with principal quantum numbers n = 6−14 is observed. A Rydberg wavepacket appearing in this case proved stable with respect to ionization; i.e., the atomic
system in strong low-frequency electromagnetic fields becomes stable with respect to ionization. The physical reasons behind
the stabilization are discussed. 相似文献
8.
Non-relativistic energies of 1s22s and 1s2
np (n⩽9) states for Co24+ ion are calculated by using the full-core plus correlation method. Our results of 1s22s and 1s22p states agree well with the high-precision results of Yan et al. Based on calculating the first-order corrections to the
energy from relativistic and mass-polarization effects, we estimate the higher-order relativistic contribution and QED correction
to the energy under a hydrogenic approximation. The transition energies, wavelengths and oscillator strengths for the 1s22s−1s2
np (n⩽9) transitions of this ion are calculated. The results agree with the experimental data available in literature satisfactorily.
By combining with quantum defect theory, our theoretical predictions on the energy and oscillator strength of this ion are
extrapolated to the whole energy region including continuous states. 相似文献
9.
L. I. Korovin I. G. Lang S. T. Pavlov 《Journal of Experimental and Theoretical Physics》1999,89(4):764-774
Combined polaron states in a rectangular quantum well in a strong magnetic field perpendicular to the well plane are discussed.
These states are due to interaction between two discrete electron levels with different Landau quantum numbers (n and n
1) and different size-quantization quantum numbers (m and m
1) on the one hand and a confined LO phonon on the other under conditions of low temperature when the energy difference between
the electronic levelsis equal or close to the energy of the confined LO phonon. The expression for the resonant magnetic field
H
res at which a combined polaron is formed contains the energy difference between size-quantized levels, so it is a function of
quantum well parameters. The separation ΔE
res between branches in the energy spectrum of a combined polaron and H
res has been calculated as a function of the quantum well width d. The resonant field H
res can be reduced dramatically in comparison with the case m=m
1. The case of size-quantization with n=n
1 has been analyzed. The energy difference ΔE
res is in the range (1–5)· 10−3 eV. The damping of combined polaron states due to the effect of anharmonicity on the LO phonon has been studied. Interband
absorption and features in the reflection spectrum due to interband transitions have been calculated for an arbitrary ratio
between the radiative and “phonon” lifetime of a combined polaron have been investigated.
Zh. éksp. Teor. Fiz. 116, 1419–1439 (October 1999) 相似文献
10.
强磁场下的重粒子碰撞激发过程是重要的非弹性碰撞过程, 但相关研究还几乎是空白. 应用经典蒙特卡洛的方法在得到无磁场下He2++H(1s)的碰撞激发截面的基础上, 详细研究了不同强度的纵向和横向强磁场环境下到不同主量子数n和磁量子数m的碰撞激发过程的态选择截面. 同时用非微扰量子方法, 得到了强磁场下靶原子的能级, 并分析了其随磁场强度变化的原因. 对碰撞过程发现由于磁场的引入导致到不同m态的激发截面有较大的分离, 同时在较低入射能区的态选择截面变化行为与磁场方向有很大关系, 这与能级变化及横向强磁场所特有的抗磁项的相互竞争有密切联系. 通过对有关事例、径迹的分析, 解释了这些变化形成的原因. 也发现由于核的运动, 沿磁场方向的轨道角动量并非绝对守恒, 而有微小的变化.
关键词:
重粒子碰撞激发
经典蒙特卡洛模拟
强磁场
态选择截面 相似文献
11.
The influence of neutral species in the E- and D-layers of the Earth’s upper atmosphere on the spectrum of the spontaneous emission (absorption) of Rydberg atoms and molecules
for transitions that occur without changing the principal quantum number (Δn = 0) is examined. Along with the process of l-mixing, the splitting of orbitally degenerate states due to interaction with perturbing neutral species of the medium is
taken into account. The possible types of radiative transitions between them are analyzed. It is demonstrated that, for principal
quantum numbers of n = 10–30, decimeter-band radiation corresponds to transitions between the levels of split states, whereas meter-band radiation,
to transitions between their individual components. It is established that, for these values of n, the ratios of the intensities of the decimeter and meter bands for Δn = 0 transitions to the intensity of IR radiation (Δn = 1) are 10−4 and 10−6, respectively. The issue of satellite signal phase shift because of multiple Raman scattering in the D-layer of the atmosphere is discussed. 相似文献
12.
V. D. Ovsyannikov V. V. Chernushin 《Journal of Experimental and Theoretical Physics》1999,89(4):618-631
We study the effect of diamagnetic interaction on the probability of radiative transitions of an atom from states split by
a field. We write the analytic expressions for the diamagnetic corrections to the matrix elements of transitions belonging
to the Lyman and Balmer series and of transitions between arbitrary nondegenerate states in hydrogen. We also discuss the
perturbation theory for transitions from degenerate diamagnetic states. The theory is based on expanding in powers of the
field strength the eigenfunctions and eigenvalues of the matrix of diamagnetic interaction in the subspace of states with
given principal and magnetic quantum numbers. The field changes the coefficients in both the superposition and the degenerate
basis. To derive the analytic expressions for the higher-order matrix elements, we use the Sturm expansion of the reduced
Coulomb Green’s function. We also elaborate on the features of the frequency dependence of the corrections to the radiative
matrix elements, which correlate with the structure of the diamagnetic spectrum of excited levels. Finally, we establish that
the magnetic field acts selectively on the diamagnetic components of emission lines: as the field strength increases, an increase
in the intensity of certain lines is accompanied by a decrease in the intensity of the other lines.
Zh. éksp. Teor. Fiz. 116, 1161–1183 (October 1999) 相似文献
13.
No Heading We show that the Dirac-von Neumann formalism for quantum mechanics can be obtained as an approximation of classical statistical
field theory. This approximation is based on the Taylor expansion (up to terms of the second order) of classical physical
variables – maps f : Ω → R, where Ω is the infinite-dimensional Hilbert space. The space of classical statistical states consists of Gaussian measures
ρ on Ω having zero mean value and dispersion σ2(ρ) ≈ h. This viewpoint to the conventional quantum formalism gives the possibility to create generalized quantum formalisms based
on expansions of classical physical variables in the Taylor series up to terms of nth order and considering statistical states ρ having dispersion σ2(ρ) = hn (for n = 2 we obtain the conventional quantum formalism). 相似文献
14.
An attempt is made to study the interaction Hamiltonian,H
int =Gψ
2(x)U(φ(x)) in the Bethe-Salpeter framework for the confined states of theψ particles interactingvia the exchange of theU field, whereU(φ) = cos (gφ). An approximate solution of the eigenvalue problem is obtained in the instantaneous approximation by projecting the Wick-rotated
Bethe-Salpeter equation onto the surface of a four-dimensional sphere and employing Hecke’s theorem in the weak-binding limit.
We find that the spectrum of energies for the confined states,E =2m+B (B is the binding energy), is characterized byE ∼n
6, wheren is the principal quantum number. 相似文献
15.
16.
N. N. Loshkareva Yu. P. Sukhorukov S. V. Naumov N. I. Solin I. B. Smolyak E. V. Panfilova 《JETP Letters》1998,68(1):97-100
In a study of the infrared optical absorption spectra of polycrystalline La1−x
CaxMnO3 (0.1⩽x⩽0.8), a contribution from free charge carriers is observed below the Curie temperature for compositions with x⩽0.4. The existence of this contribution for samples with a high resistivity is a direct proof of the existence of “metallic”
drops in an insulating matrix. The relative volume of the “metallic” phase is estimated.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 1, 89–92 (10 July 1998) 相似文献
17.
A study is reported of the thermoelectric and galvanomagnetic properties of n-Bi2Te3−x−y
SexSey solid solutions for 0.12⩽x⩽0.36 and 0.12⩽y⩽0.21 within the 80–300 K temperature region. The thermoelectric figure-of-merit Z has been found to correlate with the parameters of the many-valley energy-band model including anisotropic carrier scattering.
It is shown that a decrease in the constant-energy surface anisotropy and scattering anisotropy results in a growth of Z for optimum carrier concentrations in the solid solution.
Fiz. Tverd. Tela (St. Petersburg) 41, 187–192 (February 1999) 相似文献
18.
Converging lower bound to the critical screening parameterD
c
associated with the ground state of a two-particle system interacting through a cut-off Coulomb potential is obtained analytically
using an improved condition for the absence of bound states. The predicted numerical result for the lower bound is found to
be within 10−3% of the exact result. On the other hand, a multi-parameter variational approach yields a tight upper bound, within 0.54%
of the exact result. It is shown that the critical screening parameter for the exciteds-states can also be determined in an approximate way. We obtainD
c
ms
≈ [0.764435n
−2+0.617737n
−3]−1 wheren is the principal quantum number. The predictedD
c
for various quantum states (n=1 to 8) are in good agreement with the values obtained numerically by Singh and Varshni. 相似文献
19.
N. S. Malyshev G. V. Golubkov M. G. Golubkov R. J. Buenker H. P. Lieberman 《Russian Journal of Physical Chemistry B, Focus on Physics》2011,5(6):931-939
The potential curves of the nl(2Λ) electronically excited states of the K**-He quasimolecule (n, l, and Λ are the principal quantum number, angular momentum, and its projection on the molecular axis) are calculated. To describe
the interaction of the weakly bound electron with the singly charged potassium ion and the ground-state helium atom (with
taking into account their long-range electrostatic interactions), the formalism of two-center scattering theory and the finite-range
pseudopotential method are used. A comparison with the results of calculations performed by the MRD CI method is carried out.
The findings showed that, for small principal quantum numbers n, these methods complement each other, because the first is more reliable for large interatomic distances, R ≥ n, whereas second for small, R < n. The characteristic features of the behavior of the potential curves of the K**-He quasimolecule at large n and l are discussed. 相似文献
20.
Heinrich Saller 《International Journal of Theoretical Physics》1997,36(12):2783-2826
Quantum mechanical operators and quantum fields are interpreted as realizations of timespace manifolds. Such causal manifolds
are parametrized by the classes of the positive unitary operations in all complex operations, i.e., by the homogenous spacesD(n)=GL(C
R
n
)/U(n) withn=1 for mechanics andn=2 for relativistic fields. The rankn gives the number of both the discrete and continuous invariants used in the harmonic analysis, i.e., two characteristic masses
in the relativistic case. ‘Canonical’ field theories with the familiar divergencies are inappropriate realizations of the
real 4-dimensional causal manifoldD(2). Faithful timespace realizations do not lead to divergencies. In general they are reducible, but nondecomposable—in addition
to representations with eigenvectors (states, particle), they incorporate principal vectors without a particle (eigenvector)
basis as exemplified by the Coulomb field.
In theorthogonal andunitary groupsO(N
+,N
−), respectively, thepositive orthogonal and unitary ones areO(N) andU(N), respectively. 相似文献