All-optical implementation of collision-based evolutions of open quantum systems

Abstract

We present a new optical scheme enabling the implementation of highly stable and configurable non-Markovian dynamics. Here one photon qubit can circulate in a multipass bulk geometry consisting of two concatenated Sagnac interferometers to simulate the so called collisional model, where the system interacts at discrete times with a vacuum environment. We show the optical features of our apparatus and three different implementations of it, replicating a pure Markovian scenario and two non-Markovian ones, where we quantify the information backflow by tracking the evolution of the initial entanglement between the system photon and an ancillary one.

Quantum synchronization in a collision model

“…Among numerous ways to simulate open quantum systems, collision models have recently attracted considerable attention due to their versatility in modeling different regimes of the dynamics, such as with or without memory [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48], which is much harder to implement with other approaches. In a collision model framework, the environment is constituted by a number of particles, which can be both finite dimensional and continuous variable, and the dynamics of the system is determined by its sequential interaction with these environmental units.…”

“…Along with the described basic setting that yields a Markovian time evolution for the system, one can simply introduce intra-environment collisions to simulate a non-Markovian dynamics as well. Following the discussions on the memory effects and owing to their highly adoptable nature, quantum collision models have served as a test-bed for various ideas in several different fields, such as quantum optics [41], quantum thermodynamics [49][50][51][52][53], quantum control [54,55], and recently their all-optical experimental implementation has been demonstrated [48].…”

Precursors of non-Markovianity

“…While considerably less well studied, the case of CV collision models provides an interesting platform for the realization and study of non-Markovianity, particularly in light of the remarkable advances in the manipulation of CV systems for simulating open quantum system dynamics [54][55][56]. Inline with the DV analysis, we initialize all ancillary modes in the vacuum state.…”

Experimental Investigation of Superdiffusion via Coherent Disordered Quantum Walks

“…This particular configuration allows to create in the x−y horizontal plane of Fig. 3 a (quasi) infinite loop, which is equivalent to a chain of phase-stable and independently tunable Mach-Zehnder interferometers [24]. The entire BS network necessary for a QW is realized by exploiting also the z direction.…”

“…The output modes of each step can be extracted for measurement by a set of Moving Mirros (MMs), intersecting and extracting from the setup only the modes at the selected step N j , without intersecting the steps N < N j . The extracted radiation is then coupled on a single mode fiber and measured (for further details on the setup see [24] and [25]). A slight modification of the setup allows to inject two distinguishable or indistinguishable photons through the two different input ports of BS 1 .…”