Higher spin vortical zilches from Kubo formulae

We compute thermal one-point functions in Maxwell's theory sourced by vorticity for the zilch and its higher spin extensions via the Kubo formalism. This leads to a generalization of the recent results of [M. N. Chernodub, A. Cortijo, and K. Landsteiner, Phys. Rev. D 98, 065016 (2018)PRVDAQ2470-001010.1103/PhysRevD.98.065016] to any spin, and their value suggests a relation with possible anomalies for the higher spin tower of currents.This work is supported by FPA2015-65480-P (MINECO/FEDER,UE) and by the Spanish Research Agency (Agencia Estatal de Investigación) through the grant IFT Centro de Excelencia Severo Ochoa SEV-2016-0597. The work of J. F.-P. is supported by fellowship SEV-2012-0249-03. The work of C. C. is funded by Fundación La Caixa under “La Caixa- Severo Ochoa” international predoctoral gran

Anomalous transport in hydrodynamics and gauge/gravity duality out of equilibrium

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Teórica. Fecha de lectura: 22-11-201

Axial Hall effect and universality of holographic Weyl semi-metals

The holographic Weyl semimetal is a model of a strongly coupled topological semi-metal. A topological quantum phase transition separates a topological phase with non-vanishing anomalous Hall conductivity from a trivial state. We investigate how this phase transition depends on the parameters of the scalar potential (mass and quartic self coupling) finding that the quantum phase transition persists for a large region in parameter space. We then compute the axial Hall conductivity. The algebraic structure of the axial anomaly predicts it to be 1/3 of the electric Hall conductivity. We find that this holds once a non-trivial renormalization effect on the external axial gauge fields is taken into account. Finally we show that the phase transition also occurs in a top-down model based on a consistent truncation of type IIB supergravity.Comment: 27 pages, 9 figures, v2: references added, some typos fixed; v3 minor change

Universal fidelity reduction of quantum operations from weak dissipation

Quantum information processing is in real systems often limited by dissipation, stemming from remaining uncontrolled interaction with microscopic degrees of freedom. Given recent experimental progress, we consider weak dissipation, resulting in a small error probability per operation. Here, we find a simple formula for the fidelity reduction of any desired quantum operation. Interestingly, this reduction is independent of the specific operation; it depends only on the operation time and the dissipation. Using our formula, we investigate the situation where dissipation in different parts of the system have correlations, which is detrimental for the successful application of quantum error correction. Surprisingly, we find that a large class of correlations gives the same fidelity reduction as uncorrelated dissipation of similar strength.Comment: 5+4 page

Out of equilibrium chiral magnetic effect and momentum relaxation in holography

Peer reviewe

Lista florística actualizada de la península de Guanahacabibes, Cuba

The Guanahacabibes peninsula flora has been widely studied, both before its declaration as a Biosphere Reserve, and subsequent to this appointment; based on a review of different informative sources, systematic reports and continuous field work by the authors, an updated floristic list of the area occupied by the peninsula is presented, which shows a list of 735 species grouped into 433 genera and 124 families. It recognizes 25% of endemism, with 184 species in some of the consigned categories: 12 local endemics, 29 endemic from western Cuba and 143 endemic of all Cuba. There are also 57 exotic species present. The floristic relations are analyzed with other areas of the country and geographical region, highlighting the Yucatan peninsula, Viñalense phytogeographic district and "Sierra del Rosario" Biosphere Reserve, obtaining 18.3; 61.2 and 33.5% affinities respectively. The neotropical character of the present flora is recognized (40.4% of the total). 352 species with certain degrees of threat are identified. These results make it possible to reinforce conservation management in the peninsula.La flora de la península de Guanahacabibes ha sido ampliamente estudiada, tanto antes de su declaración como Reserva de la Biosfera, como posterior a este nombramiento; partiendo de una revisión de diferentes fuentes informativas, reportes sistemáticos y trabajos de campo continuados de los autores, se presenta una lista florística actualizada del área que ocupa la península, la cual muestra una relación de 735 especies agrupadas en 433 géneros y 124 familias. Se reconoce el 25% de endemismo, con 184 especies en alguna de las categorías consignadas: 12 endémicos locales, 29 endémicos de Cuba occidental y 143 endémicos pancubanos. Están presentes además 57 especies exóticas. Se analizan las relaciones florísticas otras áreas del país y región geográfica, destacando la península de Yucatán, distrito fitogeográfico Viñalense y Reserva de la Biosfera “Sierra del Rosario”, obteniéndose 18,3; 61,2 y 33,5% de afinidades respectivamente. Se reconoce el carácter neotropical de la flora presente (40.4% del total). Se identifican 352 especies con determinados grados de amenaza. Tales resultados posibilitan reforzar la gestión de conservación en la península

Anomalous transport and holographic momentum relaxation

Abstract The chiral magnetic and vortical effects denote the generation of dissipationless currents due to magnetic fields or rotation. They can be studied in holographic models with Chern-Simons couplings dual to anomalies in field theory. We study a holographic model with translation symmetry breaking based on linear massless scalar field backgrounds. We compute the electric DC conductivity and find that it can vanish for certain values of the translation symmetry breaking couplings. Then we compute the chiral magnetic and chiral vortical conductivities. They are completely independent of the holographic disorder couplings and take the usual values in terms of chemical potential and temperature. To arrive at this result we suggest a new definition of energy-momentum tensor in presence of the gravitational Chern-Simons coupling

Extensive characterization of a family of efficient three-qubit gates at the coherence limit

While all quantum algorithms can be expressed in terms of single-qubit and two-qubit gates, more expressive gate sets can help reduce the algorithmic depth. This is important in the presence of gate errors, especially those due to decoherence. Using superconducting qubits, we have implemented a three-qubit gate by simultaneously applying two-qubit operations, thereby realizing a three-body interaction. This method straightforwardly extends to other quantum hardware architectures, requires only a "firmware" upgrade to implement, and is faster than its constituent two-qubit gates. The three-qubit gate represents an entire family of operations, creating flexibility in quantum-circuit compilation. We demonstrate a gate fidelity of $97.90\%$, which is near the coherence limit of our device. We then generate two classes of entangled states, the GHZ and W states, by applying the new gate only once; in comparison, decompositions into the standard gate set would have a two-qubit gate depth of two and three, respectively. Finally, we combine characterization methods and analyze the experimental and statistical errors on the fidelity of the gates and of the target states.Comment: 19 pages, 10 figure

Building blocks of a flip-chip integrated superconducting quantum processor

We have integrated single and coupled superconducting transmon qubits into flip-chip modules. Each module consists of two chips -- one quantum chip and one control chip -- that are bump-bonded together. We demonstrate time-averaged coherence times exceeding $90\,\mu s$, single-qubit gate fidelities exceeding $99.9\%$, and two-qubit gate fidelities above $98.6\%$. We also present device design methods and discuss the sensitivity of device parameters to variation in interchip spacing. Notably, the additional flip-chip fabrication steps do not degrade the qubit performance compared to our baseline state-of-the-art in single-chip, planar circuits. This integration technique can be extended to the realisation of quantum processors accommodating hundreds of qubits in one module as it offers adequate input/output wiring access to all qubits and couplers.Comment: 33 pages, 12 figures, includes supplementary materials, updated with further calculations on participation ratio and Purcell limi