Geometrical and topological properties of quantum ground state manifolds permit 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 this 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.

• Received 14 February 2018
• Revised 3 April 2018

DOI:https://doi.org/10.1103/PhysRevB.97.195138