@article {Acin2006,
title = {Secrecy properties of quantum channels},
journal = {Physical Review A (Atomic, Molecular, and Optical Physics)},
volume = {73},
number = {1},
year = {2006},
month = {01/2006},
pages = {012327{\textendash}5},
keywords = {information theory, protocols, quantum cryptography},
doi = {10.1103/PhysRevA.73.012327},
url = {http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal\&id=PLRAAN000073000001012327000001\&idtype=cvips\&gifs=yes},
author = {Ac{\'\i}n, Antonio and Bae, J. and Bagan, Emili and Baig, Mari{\`a} and Masanes, Llu{\'\i}s and Mu{\~n}oz-Tapia, Ramon}
}
@article {Osterloh2005,
title = {Cold Atoms in Non-Abelian Gauge Potentials: From the Hofstadter "Moth" to Lattice Gauge Theory},
journal = {Physical Review Letters},
volume = {95},
number = {1},
year = {2005},
month = {06/2005},
pages = {010403},
publisher = {American Physical Society},
abstract = {We demonstrate how to create artificial external non-Abelian gauge potentials acting on cold atoms in optical lattices. The method employs atoms with k internal states, and laser assisted state sensitive tunneling, described by unitary k{\texttimes}k matrices. The single-particle dynamics in the case of intense U(2) vector potentials lead to a generalized Hofstadter butterfly spectrum which shows a complex mothlike structure. We discuss the possibility to realize non-Abelian interferometry (Aharonov-Bohm effect) and to study many-body dynamics of ultracold matter in external lattice gauge fields.},
issn = {0031-9007},
doi = {10.1103/PhysRevLett.95.010403},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.95.010403},
author = {Osterloh, K. and Baig, Mari{\`a} and Santos, L. and Zoller, P. and Lewenstein, Maciej}
}
@article {Acin2005,
title = {Multiple-copy two-state discrimination with individual measurements},
journal = {Physical Review A (Atomic, Molecular, and Optical Physics)},
volume = {71},
number = {3},
year = {2005},
pages = {032338},
keywords = {state discrimination},
doi = {10.1103/PhysRevA.71.032338},
url = {http://link.aps.org/abstract/PRA/v71/e032338},
author = {Ac{\'\i}n, Antonio and Bagan, Emili and Baig, Mari{\`a} and Masanes, Llu{\'\i}s and Mu{\~n}oz-Tapia, Ramon}
}
@article {Bagan2004,
title = {Collective versus local measurements in a qubit mixed-state estimation},
journal = {Physical Review A (Atomic, Molecular, and Optical Physics)},
volume = {69},
number = {1},
year = {2004},
month = {01/2004},
pages = {010304},
publisher = {American Physical Society},
abstract = {We discuss the problem of estimating a qubit mixed state. We give the optimal estimation that can be inferred from any given set of measurements. For collective measurements and for a large number N of copies, we show that the error in the estimation varies as 1/N. For local measurements, we focus on the simpler case of states lying on the equatorial plane of the Bloch sphere. We show that the error using plain tomography varies as 1/N1/4, while our approach leads to an error proportional to 1/N3/4.},
issn = {1050-2947},
doi = {10.1103/PhysRevA.69.010304},
url = {http://link.aps.org/doi/10.1103/PhysRevA.69.010304},
author = {Bagan, Emili and Baig, Mari{\`a} and Mu{\~n}oz-Tapia, Ramon and Rodriguez, A.}
}
@article {Bagan2004a,
title = {Entanglement-assisted alignment of reference frames using a dense covariant coding},
journal = {Physical Review A (Atomic, Molecular, and Optical Physics)},
volume = {69},
number = {5},
year = {2004},
month = {05/2004},
pages = {050303},
publisher = {American Physical Society},
abstract = {We present a procedure inspired by dense coding, which enables a highly efficient transmission of information of a continuous nature. The procedure requires the sender and the recipient to share a maximally entangled state. We deal with the concrete problem of aligning reference frames or trihedra by means of a quantum system. We find the optimal covariant measurement and compute the corresponding average error, which has a remarkably simple close form. The connection of this procedure with that of estimating unitary transformations on qubits is briefly discussed.},
issn = {1050-2947},
doi = {10.1103/PhysRevA.69.050303},
url = {http://link.aps.org/doi/10.1103/PhysRevA.69.050303},
author = {Bagan, Emili and Baig, Mari{\`a} and Mu{\~n}oz-Tapia, Ramon}
}
@article {Baig2004,
title = {Fixed boundary conditions analysis of the 3d gonihedric Ising model with k=0},
journal = {Physics Letters B},
volume = {585},
number = {1-2},
year = {2004},
pages = {180{\textendash}186},
abstract = {The gonihedric Ising model is a particular case of the class of models defined by Savvidy and Wegner intended as discrete versions of string theories on cubic lattices. In this Letter we perform a high statistics analysis of the phase transition exhibited by the 3d gonihedric Ising model with k=0 in the light of a set of recently stated scaling laws applicable to first order phase transitions with fixed boundary conditions. Even though qualitative evidence was presented in a previous paper to support the existence of a first order phase transition at k=0, only now are we capable of pinpointing the transition inverse temperature at $\beta$c=0.54757(63) and of checking the scaling of standard observables.},
keywords = {Author Keywords: Spin systems, Fixed boundary conditions, Gonihedric models, Phase transitions},
doi = {10.1016/j.physletb.2004.02.002},
url = {http://www.sciencedirect.com/science?\_ob=ArticleURL\&\_udi=B6TVN-4BSN95Y-3\&\_user=1517286\&\_coverDate=04\%2F08\%2F2004\&\_rdoc=1\&\_fmt=high\&\_orig=search\&\_sort=d\&\_docanchor=\&view=c\&\_acct=C000053449\&\_version=1\&\_urlVersion=0\&\_userid=1517286\&md5=b8fb559f9},
author = {Baig, Mari{\`a} and Clua, J. and Johnston, D. A. and Villanova, R.}
}
@article {Bagan2004b,
title = {Quantum reverse engineering and reference-frame alignment without nonlocal correlations},
journal = {Physical Review A (Atomic, Molecular, and Optical Physics)},
volume = {70},
number = {3},
year = {2004},
month = {09/2004},
pages = {030301},
publisher = {American Physical Society},
abstract = {The estimation of unknown qubit elementary gates and the alignment of reference frames are formally the same problem. Using quantum states made out of N qubits, we show that the theoretical precision limit for both problems, which behaves as 1/N2, can be asymptotically attained with a covariant protocol that exploits the quantum correlation of internal degrees of freedom instead of the more fragile entanglement between distant parties. This cuts by half the number of qubits needed to achieve the precision of the dense covariant coding protocol.},
issn = {1050-2947},
doi = {10.1103/PhysRevA.70.030301},
url = {http://link.aps.org/doi/10.1103/PhysRevA.70.030301},
author = {Bagan, Emili and Baig, Mari{\`a} and Mu{\~n}oz-Tapia, Ramon}
}
@conference {Bagan2003a,
title = {Optimal reconstruction of a pure qubit state with local measurements},
booktitle = {Proceedings of the 8th ICSSUR},
year = {2003},
publisher = {Rinton Press (2003)},
organization = {Rinton Press (2003)},
author = {Bagan, Emili and Baig, Mari{\`a} and Monras, Alex and Mu{\~n}oz-Tapia, Ramon}
}
@article {Bagan2001b,
title = {Aligning Reference Frames with Quantum States},
journal = {arXiv},
year = {2001},
url = {http://arxiv.org/abs/quant-ph/0106155},
author = {Bagan, Emili and Baig, Mari{\`a} and Mu{\~n}oz-Tapia, Ramon}
}