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arXiv · hep-th/9110074

A Two Parameter Deformation of the SU(1/1) Superalgebra and the XY Quantum Chain in a Magnetic Field

Haye Hinrichsen·Vladimir Rittenberg
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Abstract

We show that the XY quantum chain in a magnetic field is invariant under a two parameter deformation of the SU(1/1) superalgebra. One is led to an extension of the braid group and the Hecke algebra which reduce to the known ones when the two parameter coincide. The physical significance of the two parameters is discussed.

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Haye Hinrichsen, Vladimir Rittenberg. 1991-10-30. A Two Parameter Deformation of the SU(1/1) Superalgebra and the XY Quantum Chain in a Magnetic Field. https://doi.org/10.1016/0370-2693(92)91601-5

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