Experimental investigation of initial system-environment correlations via trace-distance evolution

Abstract

The trace distance between two states of an open quantum system quantifies their distinguishability and, for a fixed environmental state, can increase above its initial value only in the presence of initial system-environment correlations. We provide experimental evidence of such a behavior. In our all-optical apparatus, we exploit spontaneous parametric down conversion as a source of polarization entangled states and a spatial light modulator to introduce in a general fashion correlations between the polarization and the momentum degrees of freedom, which act as environment.

Unification of witnessing initial system-environment correlations and witnessing non-Markovianity

“…Many witnesses have been proposed to detect non-Markovianity [8][9][10][11][12][13]. Also, there has been proposals for witnesses that detect initial system-environment correlations [14,15], and have motivated experimental investigations [16]. The witnesses for these properties share many similar properties, but their connection has not been established.…”

Purification-based metric to measure the distance between quantum states and processes

“…Experiments on initial system-environment correlations can be found in Refs. [40] and [41]. Examples of an exact reduced dynamics which fail contractivity with respect to the trace distance are presented in Refs.…”

Collapse and revival of quantum coherence for a harmonic oscillator interacting with a classical fluctuating environment

“…On the other hand, the Markov assumption is violated in several situations of interest, e.g. in biological, optical, or solid-state systems [38][39][40][41], where a more detailed description of the environment, including the spectral structure and the inherent memory effects, is required [42][43][44][45]. In this regime, decoherence may be less detrimental and the dynamics may even induce recoherence.…”