Experimental quantum networking protocols via four-qubit hyperentangled Dicke states.

We report the experimental demonstration of two quantum networking protocols, namely quantum 1→3 telecloning and open-destination teleportation, implemented using a four-qubit register whose state is encoded in a high-quality two-photon hyperentangled Dicke state. The state resource is characterized using criteria based on multipartite entanglement witnesses. We explore the characteristic entanglement-sharing structure of a Dicke state by implementing high-fidelity projections of the four-qubit resource onto lower-dimensional states. Our work demonstrates for the first time the usefulness of Dicke states for quantum information processing.

Experimental realization of optimal noise estimation for a general Pauli channel.

We present the experimental realization of the optimal estimation protocol for a Pauli noisy channel. The method is based on the generation of 2-qubit Bell states and the introduction of quantum noise in a controlled way on one of the state subsystems. The efficiency of the optimal estimation, achieved by a Bell measurement, is shown to outperform quantum process tomography.

Hyperentangled mixed phased Dicke states: optical design and detection.

A recently introduced family of multipartite entangled states, the 4-qubit phased Dicke states, has been created by 2-photon hyperentanglement. Our experimental method allows high state fidelity and generation rate. By introducing quantum noise in the multipartite system in a controlled way, we have tested the robustness of these states. To this purpose the entanglement of the resulting multipartite entangled mixed states has been verified by using a new kind of structural witness.

Fingerprint on trigger: A real case.

The results obtained by employing a usual technique for latent prints development on firearms are presented. A fingermark on a trigger was enhanced and this print was used to identify the person who handled the firearm. Indeed, it is not usual to find a useful fingermark in that position and, more in general, on firearms because of many different factors described in the following sections. The uniqueness of the results reported in this paper allow to consider the present casework as very interesting for the forensic community.

NIR luminescence for the inspection of thermal paper: a novel tool for fingermarks detection.

The near infrared (NIR) spectral region could offer advantages over the visible region in the detection of latent fingermarks due to the enhanced contrast between the background and the print. In this present paper, this spectral range of the electromagnetic spectrum was explored in order to study the possibility to make feasible the inspection of forensic evidences when the substrate is represented by the thermal paper, which is one of the most extensively used porous surfaces for printing receipts. We successfully applied the method to thermal paper treated with several kinds of amino acid sensitive reagents. We demonstrated that, even if the treatments could cause a dark stain over the latent fingermarks, by exploiting the luminescence of thermal paper in the NIR window we were able to create a contrast otherwise impossible in the visible region.