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91.
非铁磁金属层中的量子阱态在磁输运过程中的重要性已被广泛认识.铁磁金属层中自旋极化的量子阱态以前并没有详尽的理论研究;实验上也没有清晰地观测到自旋极化量子阱态的隧穿.文章介绍了最近由卢仲毅、张晓光和Pantelides预言的Fe/MgO/FeO/Fe/Cr和其他铁磁量子阱隧道结中的共振隧穿,并解释铁、钴、铬的△1能带的对称性在这种共振隧穿中的作用. 相似文献
92.
93.
We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition,the result is explained theoretically. 相似文献
94.
L. C. Cortés-Cuautli G. F. Torres del Castillo 《International Journal of Theoretical Physics》2006,45(9):1783-1790
It is shown that, in the standard framework of non-relativistic quantum mechanics, the presence of a magnetic field implies that there are no operators representing those translations or rotations that do not leave invariant the magnetic field, and the corresponding components of the linear or angular momentum are undefined.
Pacs: 03.65.-w. 02.20.-a 相似文献
95.
We consider a four-level model for alkali metal atoms with optical pumping by nonresonant light under conditions when magnetic
dipole transitions are induced between energy sublevels of the hyperfine structure in the ground state. We present the dependences
of the observed signal as a function of the frequency detuning of the applied rf fields relative to the resonant value, calculated
in the density matrix formalism. We note the absence of a light shift in the radiofrequency-optical resonance signal, independent
of the amplitude of the rf field and the optical and thermal relaxation rates. We show that when using a modulation technique
for phase detection of the signal, its maximum discrimination ability is observed under conditions for simultaneous modulation
of the pump light intensity and the frequency of the rf field, which in principle does not occur in the classical two-level
model for optically oriented atoms in magnetic resonance.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 326–329, May–June, 2006. 相似文献
96.
ILki Kim Günter Mahler 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,54(3):405-414
We consider a single harmonic oscillator coupled to a bath
at zero temperature. As is well-known, the oscillator then has a
higher average energy than that given by its ground state. Here we
show analytically that for a damping model with arbitrarily discrete
distribution of bath modes and damping models with continuous
distributions of bath modes with cut-off frequencies, this excess
energy is less than the work needed to couple the system to the
bath, therefore, the quantum second law is not violated. On the
other hand, the second law may be violated for bath modes without
cut-off frequencies, which are, however, physically unrealistic
models.
An erratum to this article is available at . 相似文献
97.
James B. Hartle 《International Journal of Theoretical Physics》2006,45(8):1390-1396
Familiar quantum mechanics assumes a fixed spacetime geometry. Quantummechanics must therefore be generalized for quantum gravity where spacetime geometry is not fixed but rather a quantum variable. This extended abstract sketches a fully fourdimensional generalized quantum mechnics of cosmological spacetime geometries that is one such generalization.This contribution to the proceedings of the Glafka Conference is an extended abstract of the author's talk there. More details can be found in the references cited at the end of the abstract expecially (Hartle, 1995). 相似文献
98.
In the one-dimensional periodic potential case, we formulate the condition of Bloch periodicity for the reduced action by using the relation between the wave function and the reduced action established in the context of the equivalence postulate of quantum mechanics. Then, without appealing to the wave function properties, we reproduce the well-known dispersion relations which predict the band structure for the energy spectrum in the Krönig-Penney model. 相似文献
99.
In this paper we study the nature of the singularity of the Kontsevichs solution of the WDVV equations of associativity. We prove that it corresponds to a singularity in the change of two coordinates systems of the Frobenius manifold given by the quantum cohomology of CP2.
Mathematics Subject Classifications (2000) 53C99, 32D99, 14N35, 88A99. 相似文献
100.
C. S. Unnikrishnan 《Pramana》2005,65(3):359-379
I discuss in detail the result that the Bell’s inequalities derived in the context of local hidden variable theories for discrete
quantized observables can be satisfied only if a fundamental conservation law is violated on the average. This result shows
that such theories are physically nonviable, and makes the demarcating criteria of the Bell’s inequalities redundant. I show
that a unique correlation function can be derived from the validity of the conservation law alone and this coincides with
the quantum mechanical correlation function. Thus, any theory with a different correlation function, like any local hidden
variable theory, is incompatible with the fundamental conservation laws and space-time symmetries. The results are discussed
in the context of two-particle singlet and triplet states, GHZ states, and two-particle double slit interferometry. Some observations
on quantum entropy, entanglement, and nonlocality are also discussed. 相似文献