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971.
The phonon induced mechanisms of relaxation/decoherence in quantum dots are analysed. A non-perturbative technique - a modification of the Davydov transformation appropriate to the localised particles is applied for solving the electron-phonon eigenvalue problem in a quantum dot at magnetic field presence. The decay rates for polaron relaxation via the anharmonicity induced channel are analysed in details. In particular, it is indicated that previous, of perturbative type, estimations of the anharminicity induced relaxation rates were too severe and after including the coherence effects they are of, at least, one order longer. The process of exciton dressing with phonons is also analysed as the unavoidable source of picosecond scale decoherence in optically driven nanostructures. A break-down of an instant Pauli spin blocking mechanism and a large enhancement of the Fröhlich constant for confined electrons are also addressed. 相似文献
972.
ABSTRACTNonlinear propagation of dust-ion-acoustic shock waves in an unmagnetized, collisionless four-component quantum plasma containing electrons, positrons, ions and negatively charged dust grains affected by dust charge variations and viscosity of ions is studied using quantum hydrodynamic model. Considering dust charge variation give rise to calculating of charging currents of the plasma particles. These currents have been calculated with orbit limited motion theory and using Fermi-distribution functions or Boltzmann–Maxwell distribution depending on quantum or classical particles, respectively. The basic characteristics of quantum dust-ion-acoustic shock waves are investigated by deriving Korteweg–de Vries–Burgers equation under the reductive perturbation method. Depending on the relative values of the dispersive and dissipative coefficients, oscillatory and monotonic shock waves can propagate in the plasma model. The effect of chemical potential and density of dust particles on the shock wave’s height and thickness is investigated. In addition, the critical value of H (Hc) is calculated and it is shown that for R?>?0 compressive shock waves and for R?<?0 rarefactive ones can exist. The present study is applicable to researchers on quantum nonlinear structures in dense astrophysical objects and ultra-small micro- and nano-electronic devices. 相似文献
973.
974.
Let X and A be weak Hopf algebras in the sense of Li (1998). As in the case of Hopf algebras (Majid, 1990), a weak bicrossed coproduct X∞ R A is constructed by means of good regular R-matrices of the weak Hopf algebras X and A. Using this, we provide a new framework of obtaining singular solutions of the quantum Yang–Baxter equation by constructing weak quasitriangular structures over X∞ R A when both X and A admit a weak quasitriangular structure. Finally, two explicit examples are given. 相似文献
975.
In this article we study relations between groups and quantum error correcting codes. Groups of central type are used to construct quantum error correcting codes. Both stabilizer and Clifford codes can be derived from a construction involving this kind of groups. A more general construction of Clifford codes will be given and their correcting properties will be examined using group theoretical techniques. 相似文献
976.
Bárbara Pogorelsky 《代数通讯》2013,41(4):1181-1207
In this article we describe the right coideal subalgebras containing all group-like elements of the two-parameter quantum group U q (𝔤), where 𝔤 is a simple Lie algebra of type G 2, while the main parameter of quantization q is not a root of 1. As a consequence, we determine that there are precisely 60 different right coideal subalgebras containing all group-like elements. If the multiplicative order t of q is finite, t > 4, t ≠ 6, then the same classification remains valid for homogeneous right coideal subalgebras of the two-parameter version of the small Lusztig quantum group u q (𝔤). 相似文献
977.
The quantum doubles of a certain class of rank two pointed Hopf algebras are considered. The socle of the tensor product of two such modules is computed, and formulas similar to the ones in [4] are obtained. Cases when such a tensor product is completely irreducible are also given in the last section. 相似文献
978.
979.
Izuru Mori 《代数通讯》2013,41(6):2071-2091
B-construction is a way of obtaining a graded algebra from the triple consisting of an additive category, an object, and an autoequivalence, while C-construction is a way of obtaining an algebra (without unity) from the pair consisting of an additive category and a set of objects. In this article, we study and compare three important classes of algebras in noncommutative algebraic geometry and representation theory of finite dimensional algebras, namely, quantum polynomial algebras, preprojetive algebras and trivial extensions, via these constructions. 相似文献
980.
In this article, we describe the construction of Leonard pairs and Leonard triples that have q-Racah type from U q (sl 2)-modules by using equitable generators of U q (sl 2). Our result solves an open problem proposed by Terwilliger. 相似文献