“Which path” decoherence in quantum dot experiments

Abstract

We analyze and interpret recent optical experiments with semiconductor quantum dots. We derive a quantitative relation between the amount of information transferred into the environment and the optical polarization that may be observed in a spectroscopy experiment.

Optical initialization of hole spins inp-doped quantum dots: Orientation efficiency and loss of coherence

“…I. The Hamiltonian of the system under consideration in the absence of the laser field can be exactly diagonalized by application of unitary Weyl operators performing the transition into the polaron picture 33,34 …”

Complete and Partial Loss of Entanglement Due to a Phonon-Assisted Dephasing Process

“…The time evolution of the system is calculated exactly using the Weyl operator method [8,9] up to a local unitary rotation (conserving the amount of entanglement). The transformed density matrix may be written in the operator sum representation (see [10] for details)…”

Decoherence Spectroscopy for Atom Interferometry

“…Seminal studies of decoherence using matter wave interferometers [7][8][9][10][11], trapped ions [12], microwave cavities [13], superconducting circuits [14,15], and quantum dots [16,17] illustrate mechanisms that limit quantum sensors, quantum memory, and quantum information processing gate fidelity. Decoherence is usually described as a culprit that causes deleterious effects.…”