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arXiv · 1602.04168

Parameter Estimation with Dzyaloshinskii-Moriya Interaction under External Magnetic Fields

Fatih Ozaydin·Azmi Ali Altintas
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Abstract

We study the effects of external magnetic fields on the precision of parameter estimation with thermal entanglement of two spins in XX model, in the presence of Dzyaloshinskii-Moriya (DM) interaction. Calculating the quantum Fisher information, we show that homogeneous magnetic field B, inhomogeneous magnetic field b or DM interaction D increases the precision of parameter estimation, overwhelming the destructive effects of thermalization. We also show that for the model in consideration, the effects of b and D are the same. However, the existence of both b and B (or both D and B) decreases the precision. We find that in order to increase the precision in parameter estimation tasks, applying b in the ferromagnetic case and B in the antiferromagnetic case should be preferred.

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Fatih Ozaydin, Azmi Ali Altintas. 2016-02-11. Parameter Estimation with Dzyaloshinskii-Moriya Interaction under External Magnetic Fields. https://arxiv.org/abs/1602.04168

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