Environmentally Induced Entanglement -- Anomalous Behavior in the Adiabatic Regime

Understand

Considering two non-interacting qubits in the context of open quantum systems, it is well known that their common environment may act as an entangling agent.

• In a perturbative regime the influence of the environment on the system dynamics can effectively be described by a unitary and a dissipative contribution.
• For the two-spin Boson model with (sub-) Ohmic spectral density considered here, the particular unitary contribution (Lamb shift) easily explains the buildup of entanglement between the two qubits.
• Furthermore it has been argued that in the adiabatic limit, adding the so-called counterterm to the microscopic model compensates the unitary influence of the environment and, thus, inhibits the generation of entanglement.