Publications [#365312] of Harold U. Baranger

Papers Published

1. Bera, S; Florens, S; Baranger, H; Roch, N; Nazir, A; Chin, A, Unveiling environmental entanglement in strongly dissipative qubits, arXiv (January, 2013), pp. 1301.7430-1301.7430, arXiv
   (last updated on 2026/01/15)

   Abstract:
   The coupling of a qubit to a macroscopic reservoir plays a fundamental role in understanding the complex transition from the quantum to the classical world. Considering a harmonic environment, we use both intuitive arguments and numerical many-body quantum tomography to study the structure of the complete wavefunction arising in the strong-coupling regime, reached for intense qubit-environment interaction. The resulting strongly-correlated many-body ground state is built from quantum superpositions of adiabatic (polaron-like) and non-adiabatic (antipolaron-like) contributions from the bath of quantum oscillators. The emerging Schrödinger cat environmental wavefunctions can be described quantitatively via simple variational coherent states. In contrast to qubit-environment entanglement, we show that non-classicality and entanglement among the modes in the reservoir are crucial for the stabilization of qubit superpositions in regimes where standard theories predict an effectively classical spin.