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arXiv · 1805.06274

Geometrical properties of the ground state manifold in the spin boson model

Loïc Henriet
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Abstract

Geometrical and topological properties of quantum ground state manifolds permits to characterize phases of matter, and identify phase transitions. Here, we study the effect of a quantum dissipative environment on the geometrical properties of the ground state manifold of a single spin 1/2 in an external effective magnetic field. We show that the quantum phase transition at zero temperature in the model is associated with a universal metric singularity related to the divergence of the spin susceptibility. The absence of transition at finite temperature corresponds to a smooth variation of the associated metric with temperature, without singular points.

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Loïc Henriet. 2018-05-16. Geometrical properties of the ground state manifold in the spin boson model. https://doi.org/10.1103/physrevb.97.195138

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