The European Physical Journal C - We study the isentropic evolution of the matter produced in relativistic heavy-ion collisions for various values of the entropy-per-baryon ratio of interest for... 相似文献
Current researches have shown that perfect states transfer over arbitrary distances is possible for a simple unmodulated spin
chain by some schemes. The transfer of a single qubit state has been investigated in detail by Christandl et al. [Phys. Rev. Lett. 92, 187902(2004)] through a modified Heisenberg XX model Hamiltonian HG. The previous study of Christandl is restricted to the first-excitation states of HG (i.e., which correspond to the second subspace of the Hilbert space of HG). In this work, we extend their study to the case of the high-excitation states, and find that the entangled states in such
a form, | ψ 〉 = α | 00⋯ 0〉 + β | 11⋯ 1〉, can be perfectly transfered on the spin chain.
PACS numbers 03.67.Hk, 03.67.Pp, 05.50.+q. 相似文献
We present a theorem that all generalized Greenberger-Horne-Zeilinger states of a three-qubit system violate a Bell inequality in terms of probabilities. All pure entangled states of a three-qubit system are shown to violate a Bell inequality for probabilities; thus, one has Gisin's theorem for three qubits. 相似文献
The Bures fidelity between two states of a qubit quantifies the extent of which the two states are distinguished from one another. It is generated by the so called Bloch vectors, which are elements of the closed unit ball of the Euclidean 3-space. We uncover a link between the Bures fidelity and Einstein's addition in the ball, Theorem 3. We show that in terms of Einstein's addition of relativistically admissible velocities, the Bures fidelity takes a simple, elegant form, (17). This, in turn, demonstrates that the Bures fidelity is regulated by the Beltrami ball model of the hyperbolic geometry of Bolyai and Lobachevski. 相似文献
On-line high-performance liquid chromatography (HPLC) coupled with biochemical detection (BCD) has been developed to screen compounds showing antioxidant action, enzyme inhibition and receptor affinity in complex matrixes. This review summarizes HPLC methods combining different post-column detection methods, such as diode-array detection (DAD), mass spectrometry (MS), chemiluminescence (CL) and nuclear magnetic resonance, for antioxidant screening. The methods based on a single relatively stable reagent such as DPPH• and ABTS•+ were the most popular. Oxygen free radical scavengers mainly depended on post-column CL detection. The on-line hyphenated HPLC–BCD systems based on post-column UV/DAD fluorescence and MS detection were also widely applied to screen enzyme- and receptor-active compounds. These strategies provide a convenient tool for quick identification and quantification of active compounds in complex matrixes.
The non-standard Schwinger fermionic representation of the unitary group is studied by using n-fermion operators. One finds that the Schwinger fermionic representation of the U(n) group is not unique when n≥3. In general, based on n-fermion operators, the non-standard Schwinger fermionic representation of the U(n) group can be established in a uniform approach, where all the generators commute with the total number operators. The Schwinger
fermionic representation of U(Cnm) group is also discussed. 相似文献