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Graph States Under the Action of Local Clifford Group in Non-Binary Case

Mohsen Bahramgiri·Salman Beigi
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Abstract

Graph states are well-entangled quantum states that are defined based on a graph. Of course, if two graphs are isomorphic their associated states are the same. Also, we know local operations do not change the entanglement of quantum states. Therefore, graph states that are either isomorphic or equivalent under the local Clifford group have the same properties. In this paper, we first establish a bound on the number of graph states which are neither isomorphic nor equivalent under the action of local Clifford group. Also, we study graph states in non-binary case. We translate the action of local Clifford group, as well as measurement of Pauli operators, into transformations on their associated graphs. Finally, we present an efficient algorithm to verify whether two graph states, in non-binary case, are locally equivalent or not.

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Mohsen Bahramgiri, Salman Beigi. 2006-10-31. Graph States Under the Action of Local Clifford Group in Non-Binary Case. https://arxiv.org/abs/quant-ph/0610267

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