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991.
Improving the membrane model by which the entropy of the black hole is studied, we study the entropy of the black hole in the non-thermal equilibrium state. To give the problem stated here widespread meaning, we discuss the (n 2)-dimensional de Sitter spacetime. Through discussion, we obtain that the black hole‘s entropy which contains two horizons (a black hole‘s horizon and a cosmological horizon) in the non-thermal equilibrium state comprises the entropy corresponding to the black hole‘s horizon and the entropy corresponding to the cosmological horizon. Furthermore, the entropy of the black hole is a natural property of the black hole. The entropy is irrelevant to the radiation field out of the horizon. This deepens the understanding of the relationship between black hole‘s entropy and horizon‘s area. A way to study the bosonic and fermionic entropy of the black hole in high non-thermal equilibrium spacetime is given. 相似文献
992.
Chessboard-like substrates are introduced in this paper, in order to study the diffusion-limited aggregation (DLA)and the motion of poly-atoms on heterogeneous surfaces. The effect of morphology of such substrates upon the cluster aggregation is investigated using the Monte Carlo simulation. It is found that the growth process and the cluster morphology are governed by the energetic topography of the substrates. Our simulation also indicate that the island density and the fractal dimension of the clusters depend strongly on the substrate topography and the activation energy. 相似文献
993.
994.
995.
用Von Neumann熵研究了附加克尔介质的压缩真空场与二能级原子依赖强度耦合相互作用量子体系的量子纠缠特性.讨论了初始压缩真空场的压缩度以及克尔非线性作用的强度对该量子体系纠缠特性的影响.结果表明,克尔介质的非线性作用的强弱可以改变体系量子纠缠的周期性;在初始压缩度较大(r=5)时,克尔介质的非线性作用可导致原子与场持续地处于最大纠缠态,无消纠缠态或持续地处于消纠缠态.
关键词:
压缩真空态
克尔介质
依赖强度耦合J-C模型
Von Neumann熵
量子纠缠 相似文献
996.
The entropy squeezing properties for a two-level
atom interacting with a two-mode field via two different competing transitions
are investigated from a quantum information point of view. The influences
of the initial state of the system and the relative coupling strength between the atom and the field
on the atomic information entropy squeezing are discussed. Our results show that
the squeezed direction and the frequency of the information entropy squeezing
can be controlled by choosing the phase of the atom dipole and the relative competing
strength of atom-field, respectively.
We find that, under the same condition, no atomic variance squeezing is predicted from the
HUR while optimal entropy squeezing is obtained from the EUR, so the quantum information
entropy is a remarkable precision measure for the atomic squeezing
in the considered system. 相似文献
997.
998.
MA Chang-Qun GAO Chun-Yuan 《理论物理通讯》2008,50(7):180-186
K^- condensation and quark deconfinement phase transitions in neutron stars are investigated. We use the modified quark-meson coupling model for hadronic phase and the MIT bag model for quark phase. With the equation of state (EOS) solved self-consistently, we discuss the properties of neutron stars. We find that the EOS of pure hadron matter with condensed K- phase should be ruled out by the redshift for star EX00748-676, while EOS containing unpaired quark matter phase with B1/4 being about 180 MeV could be consistent with both this observation and the best measured mass of star PSR 1913 + 16. But if the recent inferred massive star among Terzan 5 with M 〉 1.68M is confirmed, all the present EOSes with condensed phase and deconfined phase would be ruled out. 相似文献
999.
ZHENG Yu-Ming FUCHS C. SRISAWAS Pornrad FAESSLER Amand YAN Yu-Peng KOBDAJ Chinorat XING Yong-Zhong 《理论物理通讯》2008,50(9):725-728
The sigma meson production in p + ^12C and p A- ^40Ca reactions at the incident energy Ep = 1.5 GeV is investigated within the Quantum Molecular Dynamics model. The simulation results indicate a distinctive A dependence of the sigma production, that is, the increase of A is followed by an increase of the production cross sections. We find that the σ meson production in proton-induced reactions is strongly medium-dependent, and the produced σ mesons decaying in a denser medium experience a stronger mass shift towards lower masses. This mass shift is an experimentally accessible observable in the final state pion pairs, which do not suffer from reabsorption by the surrounding nucleons. It is pointed out that the ratio of measured sigma cross sections as a function of the sigma invariant-mass from various reactions is a good probe to explore the existence of the σ meson in a dense nuclear environment. 相似文献
1000.
An improved transmission line model to study the thermal effects in semiconductor laser diodes is reported in this paper.
The temperature effects in the laser characteristics are obtained by incorporating temperature dependent gain and carrier
density equations for the laser cavity. These primary factors are introduced in the regular transmission line laser model
to estimate the static and dynamic characteristics of an 1.3μm InGaAsP double heterostructure laser diode. The results show
good agreement with the experimental observation and solution of rate equations referred in the literature. The key feature
of this model is that it provides the laser spectra at various temperatures. Based on the model, time dependent evolution
of optical spectrum, temperature dependent optical output and frequency chirp are evaluated. Further the distribution of photon
and electron density within the cavity is also determined. 相似文献