Multiple photon effective Hamiltonians in linear quantum optical networks

Producción CientíficaWe give an alternative derivation for the explicit formula of the effective Hamiltonian describing the evolution of the quantum state of any number of photons entering a linear optics multiport. The description is based on the effective Hamiltonian of the optical system for a single photon and comes from relating the evolution in the Lie group that describes the unitary evolution matrices in the Hilbert space of the photon states to the evolution in the Lie algebra of the Hamiltonians for one and multiple photons. Our derivation complements previous results with a point of view which reminds of the Schrödinger picture. These group theory results allow us to prove that quantum optical linear networks obey different proportionality rules which relate the expected photon number at each input and output ports. In particular, we show that for a uniform photon input the average photon number at the output is preserved for any linear multiport.Ministerio de Economía, Industria y Competitividad ( Projects TEC2015-69665-R / MTM2017-84851-C2-2-P / MTM2015-65764-C3-2-P )Junta de Castilla y León (VA089U16)Universitat Jaume I (grants P1-1B2015-02 / P1-B2016-07

Optimal approximation to unitary quantum operators with linear optics

Producción CientíficaLinear optical systems acting on photon number states produce many interesting evolutions, but cannot give all the allowed quantum operations on the input state. Using Toponogov’s theorem from differential geometry, we propose an iterative method that, for any arbitrary quantum operator U acting on n photons in m modes, returns an operator Ũ which can be implemented with linear optics. The approximation method is locally optimal and converges. The resulting operator Ũ can be translated into an experimental optical setup using previous results.Ministerio de Ciencia e Innovación- FEDER (grants PID2020-119418GB-I00 and PID2020-115930GA-I00)Junta de Castilla y León (project VA296P18)Universitat Jaume I (project UJI-B2018- 35 and grant UJI-B2018-10)Ministerio de Asuntos Económicos y Transformación Digital (grant MTM2017-84851-C2-2)Ministerios de Ciencia e Innovación y de Universidades (grant PGC2018-096446-B-C22

Security Assessment of the Spanish Contactless Identity Card

The theft of personal information to assume the identity of a person is a common threat. Individual criminals, terrorists, or crime rings normally do it to commit fraud or other felonies. Recently, the Spanish identity card, which provides enough information to hire on-line products such as mortgages or loans, was updated to incorporate a Near Field Communication (NFC) chip as electronic passports do. This contactless interface brings a new attack vector for these criminals, who might take advantage of the RFID communication to secretly steal personal information. In this paper, we assess the security of contactless Spanish identity card against identity theft. In particular, we evaluated the resistance of one of the contactless access protocol against brute-force attacks and found that no defenses were incorporated. We suggest how to avoid brute-force attacks. Furthermore, we also analyzed the pseudo-random number generator within the card, which passed all performed tests with good results.MINECO CyCriSec (TIN2014-58457-R).University of Zaragoza and Centro Universitario de la Defensa UZCUD2016-TEC-06.Project TEC2015-69665-R (MINECO/FEDER, UE)

Quantum Multiplexing with the Orbital Angular Momentum of light

The orbital angular momentum, OAM, of photons offers a suitable support to carry the quantum data of multiple users. We present two novel optical setups that send the information of n quantum communication parties through the same free-space optical link. Those qubits can be sent simultaneously and share path, wavelength and polarization without interference, increasing the communication capacity of the system. The first solution, a qubit combiner, merges n channels into the same link, which transmits n independent photons. The second solution, the OAM multiplexer, uses CNOT gates to transfer the information of n optical channels to a single photon. Additional applications of the multiplexer circuits, such as quantum arithmetic, as well as connections to OAM sorting are discussed

Universal quantum computation with the Orbital Angular Momentum of a single photon

We prove that a single photon with quantum data encoded in its orbital angular momentum can be manipulated with simple optical elements to provide any desired quantum computation. We will show how to build any quantum unitary operator using beamsplitters, phase shifters, holograms and an extraction gate based on quantum interrogation. The advantages and challenges of these approach are then discussed, in particular the problem of the readout of the results.Comment: First version. Comments welcom

Delayed commutation in quantum computer networks

In the same way that classical computer networks connect and enhance the capabilities of classical computers, quantum networks can combine the advantages of quantum information and communications. We propose a non-classical network element, a delayed commutation switch, that can solve the problem of switching time in packet switching networks. With the help of some local ancillary qubits and superdense codes we can route the information after part of it has left the network node.Comment: 4 pages. 4 figures. Preliminar versio

The CARBA-MAP study: national mapping of carbapenemases in Spain (2014–2018)

Introduction:Infections caused by carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa, including isolates producing acquired carbapenemases, constitute a prevalent health problem worldwide. The primary objective of this study was to determine the distribution of the different carbapenemases among carbapenemase-producing Enterobacterales (CPE, specifically Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae complex, and Klebsiella aerogenes) and carbapenemase-producing P. aeruginosa (CPPA) in Spain from January 2014 to December 2018.Methods: A national, retrospective, cross-sectional multicenter study was performed. The study included the first isolate per patient and year obtained from clinical samples and obtained for diagnosis of infection in hospitalized patients. A structured questionnaire was completed by the participating centers using the REDCap platform, and results were analyzed using IBM SPSS Statistics 29.0.0.Results: A total of 2,704 carbapenemase-producing microorganisms were included, for which the type of carbapenemase was determined in 2692 cases: 2280 CPE (84.7%) and 412 CPPA (15.3%), most often using molecular methods and immunochromatographic assays. Globally, the most frequent types of carbapenemase in Enterobacterales and P. aeruginosa were OXA-48-like, alone or in combination with other enzymes (1,523 cases, 66.8%) and VIM (365 cases, 88.6%), respectively. Among Enterobacterales, carbapenemase-producing K. pneumoniae was reported in 1821 cases (79.9%), followed by E. cloacae complex in 334 cases (14.6%). In Enterobacterales, KPC is mainly present in the South and South-East regions of Spain and OXA-48-like in the rest of the country. Regarding P. aeruginosa, VIM is widely distributed all over the country. Globally, an increasing percentage of OXA-48-like enzymes was observed from 2014 to 2017. KPC enzymes were more frequent in 2017–2018 compared to 2014–2016.Discussion: Data from this study help to understand the situation and evolution of the main species of CPE and CPPA in Spain, with practical implications for control and optimal treatment of infections caused by these multi-drug resistant organisms

Feasibility and short-term outcomes in liver-first approach: a Spanish snapshot study (the RENACI project)

Producción CientíficaSimple Summary: Current evidence does not provide enough information for selecting a tailored approach pathway in patients with colorectal cancer and synchronous liver metastases. There are no randomized clinical trials or prospective series comparing the classical approach with the liver-first approach. In addition, information on the proportion of patients who actually complete the therapeutic regimen is limited. The RENACI Project was a prospective National Registry performed on patients with colorectal cancer and synchronous liver metastases undergoing the liver-first approach. This study aimed to present the data of feasibility and short-term outcomes of the Spanish National Registry of Liver First Approach (the RENACI Project).(1) Background: The liver-first approach may be indicated for colorectal cancer patients with synchronous liver metastases to whom preoperative chemotherapy opens a potential window in which liver resection may be undertaken. This study aims to present the data of feasibility and short-term outcomes in the liver-first approach. (2) Methods: A prospective observational study was performed in Spanish hospitals that had a medium/high-volume of HPB surgeries from 1 June 2019 to 31 August 2020. (3) Results: In total, 40 hospitals participated, including a total of 2288 hepatectomies, 1350 for colorectal liver metastases, 150 of them (11.1%) using the liver-first approach, 63 (42.0%) in hospitals performing <50 hepatectomies/year. The proportion of patients as ASA III was significantly higher in centers performing ≥50 hepatectomies/year (difference: 18.9%; p = 0.0213). In 81.1% of the cases, the primary tumor was in the rectum or sigmoid colon. In total, 40% of the patients underwent major hepatectomies. The surgical approach was open surgery in 87 (58.0%) patients. Resection margins were R0 in 78.5% of the patients. In total, 40 (26.7%) patients had complications after the liver resection and 36 (27.3%) had complications after the primary resection. One-hundred and thirty-two (89.3%) patients completed the therapeutic regime. (4) Conclusions: There were no differences in the surgical outcomes between the centers performing <50 and ≥50 hepatectomies/year. Further analysis evaluating factors associated with clinical outcomes and determining the best candidates for this approach will be subsequently conducted.Asociación Española de Cirujanos - (grant Research Projects 2020

El eje Prado-Recoletos-Castellana: una interpretación de su papel urbano

Tesis inédita presentada en la Universidad Europea de Madrid. Escuela Superior de Arte y ArquitecturaEsta Tesis no aporta novedades desde la historia (es un eje estudiado en síntesis y en extensión; con polémicas y consensos), pero sí respecto al análisis de los papeles y los modelos urbanos del eje, las permanencias y los cambios, y en el estudio de su capacidad de adaptación (para no perder su primacía). También indaga su significación e imagen (y cómo se lee ésta en cada una de las propuestas, incluso en las más recientes; y en otras ajenas). Plantea los problemas de escala (de todo tipo: territorial, urbana, espacios concretos y elementos puntuales) y de coexistencia tipológica (en contraste muchas veces). A través del estudio más preciso de algunos episodios (y de algunos edificios) analiza la adecuación de sus mejores momentos. Condiciones, imagen y carácter: El eje tiene (desde sus orígenes, tanto en los Prados como en la Castellana) lo básico: el trazado, el arbolado, una buena escala y una magnífica sección. Es uno de los mejores espacios urbanos del mundo (y eso hace que su imagen sea positiva y se proyecte a muchos otros sitios), pese a su mala fortuna histórica (con intervenciones de todo tipo, algunas desgraciadas, y no siempre reversibles; y tantas ocasiones perdidas, en regímenes distintos (para todos importante), también con unas curiosas continuidades entre rupturas; con diferencias de carácter en sus diversos tramos (y cambiantes en el tiempo) no siempre conseguidos, y ya veremos en los que vendrán. Las prolongaciones, sucesivas directrices de Madrid: La fuerza de su imagen (que procede de modelos distintos, y que se ha reorientado varias veces) hace que a lo largo del tiempo sea la principal directriz de crecimiento y vertebración de Madrid: ideal (incluso antes de poderlo ser, en el ensanche, con el tapón del Hipódromo; en imágenes poderosas y sugestivas, de mayor o menor alcance y rotundidad, como las de Zuazo) y real (en el mercado, como símbolo). [Resumen Teseo]UE

Data for the light injection attack on QKD/QRNG

Data Supporting the results of the paper "Attacking quantum key distribution by light injection via ventilation openings". Contains example output sequences of a Quantum Random Number Generator in normal operation and under the attack and the equipment used for the experiments on the Quantum Key Distribution platform Clavis2.MINECO/FEDER, UE (project TEC2015-69665-R), Junta de Castilla y León (project VA089U16), Movilidad Investigadores UVa-Banco Santander 2015, Industry Canada, CFI, NSERC (programs Discovery and CryptoWorks21), Ontario MRI, US Office of Naval Research, and the Ministry of Education and Science of Russia (program NTI center for quantum communications)