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Developing strategies to effectively discriminate between different quantum states is a fundamental issue in quantum information and communication. The actual realization of generally optimal protocols in this task is often limited by the need of supplemental resources and very complex receivers. We have experimentally implemented two discrimination schemes in a minimum-error scenario based on a receiver featured by a network structure and a dynamical processing of information. The first protocol implemented in our experiment, directly inspired to a recent theoretical proposal, achieves binary optimal discrimination, while the second one provides a novel approach to multi-state quantum discrimination, relying on the dynamical features of the network-like receiver. This strategy exploits the arrival time degree of freedom as an encoding variable, achieving optimal results, without the need for supplemental systems or devices. Our results further reveal the potential of dynamical approaches to quantum state discrimination tasks, providing a possible starting point for efficient alternatives to current experimental strategies.

Discutir sobre Direitos Humanos e Gênero e/ou sua ausência na formação inicial e continuada de docentes tem se mostrado um desafio no avanço da educação e seu papel na formação humana. Diante desse cenário, foi realizada a revisão sistemática de literatura sobre a temática, considerando a base de dados do Portal de Periódicos da CAPES, em artigos publicados nos últimos cinco anos (2015-2020). Foram selecionados vinte artigos e organizados em grupos temáticos. Nesse viés, o estudo, pautado nos estudos das áreas da Educação, Direitos Humanos e dos Estudos de Gênero, possui caráter quanti-qualitativo e bibliográfico. Foi possível constatar situações como: a) exclusão dos temas dos currículos, b) políticas mobilizadas por determinados grupos religiosos, c) lacunas e ocultamento das temáticas na formação inicial e continuada, d) resistência e visões hegemônicas binárias e sexistas por parte das/os profissionais, e) relações de poder que reforçam a (re)produção de estereótipos, entre outros.

We propose a quantum probing protocol, a Mach-Zehnder-like interferomet-ric setup, employing quantum walks to explore quantum information spreading patterns, such as anomalous and classical transport, as well as Anderson localization.

We experimentally implemented a controllable inhomogenous Quantum Walk evolution of two photon states. Through the imposition of suitable disorder configurations, we observed an enhance-ment in quantum correlations of the system, compared to the ordered case.

The presence of disorder and inhomogeneities in quantum networks has often been unexpectedly beneficial for both quantum and classical resources. Here, we experimentally realize a controllable inhomogenous Quantum Walk dynamics, which can be exploited to investigate the effect of coherent disorder on the quantum correlations between two indistinguishable photons. Through the imposition of suitable disorder configurations, we observe two photon states which exhibit an enhancement in the quantum correlations between two modes of the network, compared to the case of an ordered Quantum Walk. Different configurations of disorder can steer the system towards different realizations of such an enhancement, thus allowing spatial and temporal manipulation of quantum correlations., Comment: 11 pages, 12 figures

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

We design a quantum probing protocol using quantum walks to investigate the quantum information spreading pattern. We employ quantum Fisher information as a figure of merit to quantify extractable information about an unknown parameter encoded within the quantum walk evolution. Although the approach is universal, we focus on the coherent static and dynamic disorder to investigate anomalous and classical transport as well as Anderson localization. We provide a feasible experimental strategy to implement, in principle, the quantum probing protocol based on the quantum Fisher information using a Mach–Zehnder-like interferometric setup. Our results show that a quantum walk can be considered as a readout device of information about defects and perturbations occurring in complex networks, both classical and quantum.

A novel bulk optics scheme for quantum walks is presented. It consists of a one-dimensional lattice built on two concatenated displaced Sagnac interferometers that make it possible to reproduce all the possible trajectories of an optical quantum walk. Because of the closed loop configuration, the interferometric structure is intrinsically stable in phase. Moreover, the lattice structure is highly configurable, as any phase component perceived by the walker is accessible, and finally, all output modes can be measured at any step of the quantum walk evolution. We report here on the experimental implementation of ordered and disordered quantum walks., This manuscript is organized in 5 sections, containing 8 pages and 7 figures

Many disordered systems show a superdiffusive dynamics, intermediate between the diffusive one, typical of a classical stochastic process, and the so called ballistic behaviour, which is generally expected for the spreading in a quantum process. We have experimentally investigated the superdiffusive behaviour of a quantum walk (QW), whose dynamics can be related to energy transport phenomena, with a resolution which is high enough to clearly distinguish between different disorder regimes. By our experimental setup, the region between ballistic and diffusive spreading can be effectively scanned by suitably setting few degrees of freedom and without applying any decoherence to the QW evolution., Comment: 5 pages, 5 figures + supplementary material

We present a bulk-optics setup for discrete quantum walks, based on a novel multipass displaced Sagnac geometry. It is phase stable, reconfigurable and allows to meausure the output radiation at each step. The experimental results of both ordered and disordered one-particle evolutions are reported.

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., This document is organized in 5 sections, containing 10 pages and 7 figures

We demonstrate the generation of states hyperentangled in polarization and path by non-degenerate spontaneous down conversion. We characterize them by quantum state tomography and stimulated emission tomography.

In this work we demonstrate the use of stimulated emission tomography to characterize a hyper-entangled state generated by spontaneous parametric down-conversion in a CW-pumped source. In particular, we consider the generation of hyper-entangled states consisting of photon pairs entangled in polarisation and path. These results extend the capability of stimulated emission tomography beyond the polarisation degree of freedom, and demonstrate the use of this technique to study states in higher dimension Hilbert spaces.