Du S.,Xiamen University |
Bai Z.,Xiamen University |
Guo Y.,Shanxi Datong University
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015
We build in this paper the counterpart of the celebrated Nielsen theorem for coherence manipulation. This offers an affirmative answer to the open question: whether, given two states ρ and σ, either ρ can be transformed into σ or vice versa under incoherent operations [Baumgratz, Phys. Rev. Lett. 113, 140401 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.140401]. As a consequence, we find that there exist essentially different types of coherence. Moreover, incoherent operations can be enhanced in the presence of certain coherent states. These extra states are coherent catalysts: they allow uncertain incoherent operations to be realized without being consumed in any way. Our main result also sheds light on the construction of coherence measures. © 2015 American Physical Society.
Ling Y.,Shanghai JiaoTong University |
Ling Y.,Shanxi Datong University |
Cai X.,Shanghai JiaoTong University
Renewable and Sustainable Energy Reviews | Year: 2012
Wind energy, as a reliable, natural and renewable electrical power supply, produces no emissions and so it is an excellent alternative to conventional, more heavily polluting fuels in the long term based on the worldwide concern about the environment and energy supply. Wind energy resources in China are affluent, but its distribution are uneven, centralized, and far from both the utility and the high electricity demand markets. This made China's onshore wind power development have such characteristics as large scale, high centralization and far transmission, which is different with that in Europe, where the characteristics are even distribution, decentralized. In past two decades, considering the economic, technical and environmental benefits of wind power, China has given priority to its development. Besides the dramatic growth of large scale grid-connected wind power, household-scale wind power has been used most successfully in remote rural regions in China. Therefore, the development of wind power will be of great importance to alleviate the energy crisis and environmental pollution resulting from the rapid economic growth of China in the future. In this paper, the current development of wind energy utilization in China is investigated, and some critical barriers are discussed. Finally, the perspective of wind energy utilization is presented, where focuses are placed on seven wind power bases. © 2012 Elsevier Ltd. All rights reserved.
Ma M.-S.,Shanxi Datong University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014
We study the effects of quantum gravitational correction on the thermodynamics of black holes in the asymptotic safety scenario. Owing to the quantum-corrected Schwarzschild metric, the thermodynamic quantities are also corrected and a Hawking-Page-type phase transition may exist. We also employ the concept of thermodynamic geometry to the black hole to characterize the phase transition. By introducing a cavity enclosing the black hole, we apply the spatially finite boundary conditions to further investigate the thermodynamic phase transition of the black hole. It is shown that the larger and small black holes are both locally stable according to heat capacity. According to free energy, we find that the quantum-corrected black hole has similar thermodynamic phase structure to that of RN-AdS black hole. In addition, we also discuss the possibility of the phase transition between the black hole and the hot curved space. Above a certain temperature T0, the black hole is more probable than the hot space. © 2014 Elsevier B.V.
Li H.-F.,Shanxi Datong University
Journal of High Energy Physics | Year: 2013
We take advantage of the Sturm-Liouville eigenvalue problem to analytically study the holographic insulator/superconductor phase transition in the probe limit. The interesting point is that this analytical method can not only estimate the most stable mode of the phase transition, but also the second stable mode. We find that this analytical method perfectly matches with other numerical methods, such as the shooting method. Besides, we argue that only Dirichlet boundary condition of the trial function is enough under certain circumstances, which will lead to a more precise estimation. This relaxation for the boundary condition of the trial function is first observed in this paper as far as we know. © 2013 SISSA, Trieste, Italy.
Ma M.-S.,Shanxi Datong University
Annals of Physics | Year: 2015
We obtain a magnetically charged regular black hole in general relativity. The source to the Einstein field equations is nonlinear electrodynamic field in a physically reasonable model of nonlinear electrodynamics (NED). "Physically" here means the NED model is constructed on the basis of three conditions: the Maxwell asymptotic in the weak electromagnetic field limit; the presence of vacuum birefringence phenomenon; and satisfying the weak energy condition (WEC). In addition, we analyze the thermodynamic properties of the regular black hole in two ways. According to the usual black hole thermodynamics, we calculate the heat capacity at constant charge, from which we know the smaller black hole is more stable. We also employ the horizon thermodynamics to discuss the thermodynamic quantities, especially the heat capacity at constant pressure. © 2015 Elsevier Inc.