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Generando entrelazamiento en cadenas XY - (Generating entanglement in XY chains)

C. T. Schmiegelow
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Abstract

Se estudia en este trabajo la capacidad de generar entrelazamiento de una cadena de espines con acoplamiento de Heisenberg XY y un campo magnetico uniforme a partir de un estado inicial en el que los espines estan completamente alineados. Se encuentra que la capacidad de generar estados entrelazados no muestra un comportamiento monotono con el campo presentando, en cambio, plateaus y resonancias. Tambien se muestra que, a pesar de que la anisotropia es necesaria para que se generen estados entrelazados, una mayor anisotropia no implica necesariamente mejores condiciones para generar entrelazamiento que sirva para usarse en una computadora cuantica. Inclusive, se observa que, se genera una cantidad finita de entrelazamiento en el limite de pequena anisotropia. (The maximum entanglement reached by an initially fully aligned state evolving in a XY Heisenberg spin chain placed in a uniform transverse magnetic field is studied. It is shown that the capacity to create entangled states (both of one qubit with the rest of the chain and pairwise between two adjacent qubits) is not a monotonous function of the magnetic field: it presents plateaus and resonances. It is also shown that, though anisotropy in the interaction is necessary for entanglement generation, the best conditions for generating entanglement that may be suitable for use in quantum computation is not that of biggest anisotropy. Moreover finite amounts of entanglement are generated in the small anisotropy limit.)

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C. T. Schmiegelow. 2006-11-27. Generando entrelazamiento en cadenas XY - (Generating entanglement in XY chains). https://arxiv.org/abs/quant-ph/0611258

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