Zobrazeno 1 - 10
of 25
pro vyhledávání: '"M P, Terra"'
Autor:
Cavalcanti, D., Saldanha, P. L., Cosme, O., Brandao, F. G. S. L., Monken, C. H., Padua, S., Santos, M. Franca, Cunha, M. O. Terra
Publikováno v:
Phys. Rev. A 78, 012318 (2008)
We show that the geometry of the set of quantum states plays a crucial role in the behavior of entanglement in different physical systems. More specifically it is shown that singular points at the border of the set of unentangled states appear as sin
Externí odkaz:
http://arxiv.org/abs/0709.0301
Publikováno v:
Phys. Rev. A 76, 042329 (2007)
The entanglement of superpositions [Phys. Rev. Lett. 97, 100502 (2006)] is generalized to the multipartite scenario: an upper bound to the multipartite entanglement of a superposition is given in terms of the entanglement of the superposed states and
Externí odkaz:
http://arxiv.org/abs/0705.2521
We address some of the most commonly raised questions about entanglement, especially with regard to so-called occupation number entanglement. To answer unambiguously whether entanglement can exist in a one-atom delocalized state, we propose an experi
Externí odkaz:
http://arxiv.org/abs/quant-ph/0606149
Autor:
Cavalcanti, D., Cunha, M. O. Terra
In spite of the fact that there are only two classes of three-qubit genuine entanglement: W and GHZ, we show that there are three-qubit genuinely entangled states which can not be detected neither by W nor by GHZ entanglement witnesses.
Comment:
Comment:
Externí odkaz:
http://arxiv.org/abs/quant-ph/0506035
Publikováno v:
Phys. Rev. A 72, 062307 (2005)
We investigate the effects of fuzzy measurements on spin entanglement for identical particles, both fermions and bosons. We first consider an ideal measurement apparatus and define operators that detect the symmetry of the spatial and spin part of th
Externí odkaz:
http://arxiv.org/abs/quant-ph/0505029
Autor:
Lemos, Gabriela Barreto, Santos, M. F., de Faria, J. G. Peixoto, Cunha, M. O. Terra, Nemes, M. C.
We use a spin-1/2 model to analyze tunnelling in a double well system coupled to an external reservoir. We consider different noise sources such as fluctuations on the height and central position of the barrier and propose an experiment to observe th
Externí odkaz:
http://arxiv.org/abs/quant-ph/0504020
A perturbative treatment of reduced density operators of quantum subsystems is implemented in the same spirit as Fermi Golden Rule for scattering. Analytic expressions for linear entropy (a measure of purity loss, and in some cases of coherence loss)
Externí odkaz:
http://arxiv.org/abs/quant-ph/0409061
Publikováno v:
Physical Review A 71, 014301 (2005)
A tomographic process for three-qubit pure states using only pairwise detections is presented.
Comment: 3 pages; revtex4; v2: the focus on tomography was emphasized and the experimental procedure detailed; v3: the text was improved in clarity, s
Comment: 3 pages; revtex4; v2: the focus on tomography was emphasized and the experimental procedure detailed; v3: the text was improved in clarity, s
Externí odkaz:
http://arxiv.org/abs/quant-ph/0408022
Publikováno v:
Physica A 341 (2004) 234-250
We give a detailed account of the derivation of a master equation for two coupled cavities in the presence of dissipation. The analytical solution is presented and physical limits of interest are discussed. Firstly we show that the decay rate of init
Externí odkaz:
http://arxiv.org/abs/quant-ph/0405022
Autor:
Cunha, M. O. Terra, Nemes, M. C.
Publikováno v:
Phys. Lett. A 329, 409-413 (2004)
Two mechanisms of decoherence in ion traps are studied, specially related to the experiment [Kielpinski et al., Science 291 (2001) 1013]. Statistical hypothesis are made about the unknown variables and the expected behaviour of the visibility of the
Externí odkaz:
http://arxiv.org/abs/quant-ph/0401117