43 research outputs found
Experimental demonstration of the DPTS QKD protocol over a 170 km fiber link
Quantum key distribution (QKD) is a promising technology aiming at solving
the security problem arising from the advent of quantum computers. While the
main theoretical aspects are well developed today, limited performances, in
terms of achievable link distance and secret key rate, are preventing the
deployment of this technology on a large scale. More recent QKD protocols,
which use multiple degrees of freedom for the encoding of the quantum states,
allow an enhancement of the system performances. Here, we present the
experimental demonstration of the differential phase-time shifting protocol
(DPTS) up to 170 km of fiber link. We compare its performance with the
well-known coherent one-way (COW) and the differential phase shifting (DPS)
protocols, demonstrating a higher secret key rate up to 100 km. Moreover, we
propagate a classical signal in the same fiber, proving the compatibility of
quantum and classical light.Comment: 5 pages, 3 figures, journal pape
Orbital angular momentum states enabling fiber-based high-dimensional quantum communication
Quantum networks are the ultimate target in quantum communication, where many
connected users can share information carried by quantum systems. The keystones
of such structures are the reliable generation, transmission and manipulation
of quantum states. Two-dimensional quantum states, qubits, are steadily adopted
as information units. However, high-dimensional quantum states, qudits,
constitute a richer resource for future quantum networks, exceeding the
limitations imposed by the ubiquitous qubits. The generation and manipulation
of such -level systems have been improved over the last ten years, but their
reliable transmission between remote locations remains the main challenge.
Here, we show how a recent air-core fiber supporting orbital angular momentum
(OAM) modes can be exploited to faithfully transmit -dimensional states.
Four OAM quantum states and their superpositions are created, propagated in a
1.2 km long fiber and detected with high fidelities. In addition, three quantum
key distribution (QKD) protocols are implemented as concrete applications to
assert the practicality of our results. This experiment enhances the
distribution of high-dimensional quantum states, attesting the orbital angular
momentum as vessel for the future quantum network
The Rapid Identification of Anoplophora chinensis (Coleoptera: Cerambycidae) From Adult, Larval, and Frass Samples Using TaqMan Probe Assay
A molecular diagnostic method using TaqMan probe qPCR is presented for the identification of Anoplophora chinensis (Förster) (Coleoptera: Cerambycidae) from whole body insects (adults and larvae) and frass samples stored under different conditions. The results showed a perfect amplification of DNA from all samples; the repeatability and reproducibility of the protocol were very good, with standard deviations of inter-run and intrarun variability less than or equal to 0.5. The assay allowed to discern all A. chinensis samples from those of the other non-target wood-borer species, with 100% correspondence to the homologous sequences. No amplification or cross reactions were observed with A. glabripennis (Motschulsky) (Coleoptera: Cerambycidae), which is the most related species among those tested. The protocol was validated by an internal blind panel test which showed a good correspondence between the results obtained by different operators in the same lab. The analytical sensitivity for the lab frass with the Probe qPCR, namely the lowest amount of A. chinensis DNA that can be detected (LoD), was 0.64 pg/μl with a Cq of 34.87. The use of indirect evidence for the identification of a pest is an important feature of the method, which could be crucial to detect the presence of wood-boring insects.
This diagnostic tool can help prevent the introduction of A. chinensis into new environments or delimit existing outbreak areas thanks to indirect frass diagnosis
Path-encoded high-dimensional quantum communication over a 2 km multicore fiber
Quantum key distribution (QKD) protocols based on high-dimensional quantum
states have shown the route to increase the key rate generation while
benefiting of enhanced error tolerance, thus overcoming the limitations of
two-dimensional QKD protocols. Nonetheless, the reliable transmission through
fiber links of high-dimensional quantum states remains an open challenge that
must be addressed to boost their application. Here, we demonstrate the reliable
transmission over a 2 km long multicore fiber of path-encoded high-dimensional
quantum states. Leveraging on a phase-locked loop system, a stable
interferometric detection is guaranteed, allowing for low error rates and the
generation of 6.3 Mbit/s of secret key rate.Comment: to appear in npj Quantum Informatio
First record of Aleurocanthus camelliae Kanmiya & Kasai, 2011 (Hemiptera, Aleyrodidae) from Italy, on ornamental Camellia spp. plants
This paper provides a first report of Aleurocanthus camelliae, the Camellia spiny whitefly, from Italy. The pest was found on plants of Camellia spp. grown in the nursery. Brief morphological and biological information is provided on this whitefly, as well as some considerations on the phytosanitary measures to be adopted to reduce the potential risk of its spread on ornamental plants in Europe and the EPPO region
Rapid Detection of Pityophthorus juglandis (Blackman) (Coleoptera, Curculionidae) with the Loop-Mediated Isothermal Amplification (LAMP) Method
The walnut twig beetle Pityophthorus juglandis is a phloem-boring bark beetle responsible, in association with the ascomycete Geosmithia morbida, for the Thousand Cankers Disease (TCD) of walnut trees. The recent finding of TCD in Europe prompted the development of effective diagnostic protocols for the early detection of members of this insect/fungus complex. Here we report the development of a highly efficient, low-cost, and rapid method for detecting the beetle, or even just its biological traces, from environmental samples: the loop-mediated isothermal amplification (LAMP) assay. The method, designed on the 28S ribosomal RNA gene, showed high specificity and sensitivity, with no cross reactivity to other bark beetles and wood-boring insects. The test was successful even with very small amounts of the target insect’s nucleic acid, with limit values of 0.64 pg/µL and 3.2 pg/µL for WTB adults and frass, respectively. A comparison of the method (both in real time and visual) with conventional PCR did not display significant differences in terms of LoD. This LAMP protocol will enable quick, low-cost, and early detection of P. juglandis in areas with new infestations and for phytosanitary inspections at vulnerable sites (e.g., seaports, airports, loading stations, storage facilities, and wood processing companies)