ar X iv : q ua nt - p h / 01 06 05 5 v 1 1 1 Ju n 20 01 Analysis of 1 and 2 Particle Quantum Systems using Geometric Algebra

ar X iv : q ua nt - p h / 05 06 09 5 v 1 1 3 Ju n 20 05 Schmidt states and positivity of linear maps

Using pure entangled Schmidt states, we show that m-positivity of a map is bounded by the ranks of its negative Kraus matrices. We also give an algebraic condition for a map to be m-positive. We interpret these results in the context of positive maps as entanglement witnesses, and find that only 1-positive maps are needed for testing entanglement.

ar X iv : q ua nt - p h / 06 06 17 6 v 1 2 1 Ju n 20 06 On quantum positive dynamical maps

The new arguments indicating that non-completely positive maps can describe open quantum evolution are given. This work was partially supported by KBN grant PB/1490/PO3/2003/25 and SCALA (IST-2004-015714) 1

ar X iv : q ua nt - p h / 05 06 01 5 v 1 2 Ju n 20 05 Reply To “ Comment on ‘ Quantum Convolutional Error - Correcting Codes ’ ”

Theorem 3. Let C1 be a classical (block or convolutional) code of rate r1 and distance d1 and let C2 be the [n2 = d2, 1, d2] majority vote classical code of rate r2, namely, the one that maps |t〉 to ⊗n2 j=1 |t〉. We construct a quantum code C by first encoding a quantum state by C1, then by applying a Hadamard transform to every resultant qubit, and finally by encoding each of the Hadamard trans...

ar X iv : q ua nt - p h / 02 06 11 6 v 1 1 8 Ju n 20 02 Five Lectures On Dissipative Master Equations

ar X iv : q ua nt - p h / 05 06 15 0 v 1 1 7 Ju n 20 05 Quantum Computing , Metrology , and Imaging

Information science is entering into a new era in which certain subtleties of quantum mechanics enables large enhancements in computational efficiency and communication security. Naturally, precise control of quantum systems required for the implementation of quantum information processing protocols implies potential breakthoughs in other sciences and technologies. We discuss recent development...