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IFISC News - Boosting the efficiency of quantum heat engines
by ifisc＠ifisc.uib-csic.es 06 May '22

06 May '22

Boosting the efficiency of quantum heat engines A team of researchers from IFISC (UIB-CSIC) has demonstrated that a quantum chiral conductor driven by an alternating current voltage can operate with efficiencies much higher than the hitherto insurmountable Carnot limit. In the paper, published in Nature Communications, the authors propose a general class of quantum devices driven periodically by alternating current (AC), which can convert heat into electricity with an increased performance. One of the implications of the second law of thermodynamics is that the power generated by an ideal thermal machine cannot exceed the Carnot efficiency limit in the classical regime. However, this upper limit can in principle be exceeded if we assume that quantum coherence is also a resource for entropy production. Therefore, understanding how the entropy resource can be controlled in different scenarios is key to achieving higher efficiency in quantum engines and refrigerators. To do so, the team considered a pumped quantum engine consisting of an arbitrary energy-dependent transmission tunneling scatterer coupled to hot and cold electronic reservoirs in the presence of an external AC bias voltage. A crucial point to understand is that most AC voltage sources inject net energy into the motor, thus reducing the power developed. The main finding of the study is to show how to cancel this detrimental effect using chiral conductors. These conductors are characterized by a spatial separation of the electronic motion, such as those created with topological matter. Then, the proposed device selectively applies an AC field to the electrons depending on their direction. This boosts the quantum engine efficiency beyond the Carnot bound. The paper discusses two necessary ingredients to observe this effect: on the one hand, an irreversible production of entropy by the photo-assisted excitation processes induced by the AC field and, on the other hand, the absence of net energy injection thanks to chirality. The device also extracts work from baths held at the same temperature, thus seemingly violating the Kelvin-Planck law. However, this does not mean that the second law of thermodynamics is not satisfied, since with a proper definition entropy production is always positive. These results are relevant within modern developments of quantum thermodynamics that aim at understanding the role of nonequilibrium effects in quantum machines.Ryu, S., López, R., Serra, L. et al. Beating Carnot efficiency with periodically driven chiral conductors. Nat Commun 13, 2512 (2022). https://doi.org/10.1038/s41467-022-30039-7Behind the Paper http://ifisc.uib-csic.es/en/news/boosting-efficiency-quantum-heat-engines/

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IFISC News - IFISC People: Alberto J. Sánchez
by ifisc＠ifisc.uib-csic.es 04 Apr '22

04 Apr '22

IFISC People: Alberto J. Sánchez We are glad to introduce Alberto J. Sánchez to the other IFISC members. Alberto has higher education in Administration and Finance and more than 10 years of experience working as Administrative performing accounting tasks. At IFISC he will perform administrative tasks, focused on accounting and payment management. You can find him in office 204. http://ifisc.uib-csic.es/en/news/ifisc-people-alberto-j-sanchez/

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IFISC News - The World-Wide Waste Web, the network through which our garbage travels
by ifisc＠ifisc.uib-csic.es 29 Mar '22

29 Mar '22

The World-Wide Waste Web, the network through which our garbage travels A group of researchers from IFISC (UIB-CSIC) led by Dr. Ernesto Estrada, has identified the list of countries with the highest risk of saturating their waste management capacity. The article, published in Nature Communications, has reconstructed the world-wide waste web, a set of global exchange networks between countries that import and export waste. The researchers defined a separate web for each of the waste types analyzed using data from the BaC (Basel Convention on the Control of Transboundary Movement of Hazardous Wastes and their Disposal) online database and matched it with each country's individual capacity to manage such waste. Between 7 and 10 billion tons of waste are produced annually worldwide. This includes between 300 and 500 million tons of hazardous waste, whether corrosive, flammable or toxic. Some of this waste does not stay in its country of origin and travels through the world-wide waste web to be processed elsewhere. This is done, on the one hand, to dispose of the waste more economically in the case of waste exporting countries, and on the other hand, to have easy access to materials collected by recycling these wastes in the case of waste importing countries. That is why the world-wide waste web is a directional and weighted network, i.e., waste travels from country A to B, but not the other way around or in the same quantity as from A to C, for example. This characteristic is evident in the great asymmetry in the import and export of hazardous waste between developed (typically exporting) and developing (typically importing) countries. However, the capacity to process these wastes is not the same for all countries, and many of them run the risk of becoming congested, i.e. importing more waste than they are able to manage without compromising the environment. To quantify this, the researchers used the Enviromental Performance Index (EPI), a ranking that indicates "which countries are best addressing the environmental challenges facing each nation" and provides information on capacity to manage different types of waste. This index, together with the structure of the world-wide waste web, makes it possible to identify those countries with a high risk of quickly becoming congested if their EPI does not match the amount of hazardous waste they import. Of the 57 countries that are at high risk, 29 of them are in Africa, 16 in Asia, 5 in the Americas, 4 in Europe and 3 in Oceania. The impact of these countries at high risk of congestion can be verified by analyzing chemical fingerprints, chemical elements generated by waste that leave quantifiable traces in the environment in the form of heavy metals, volatile organic compounds or persistent organic pollutants. Regarding the structure of the world-wide waste web, the study states that the density of connections has decreased between 2001 and 2019, in addition to observing that many countries are becoming either exclusively waste importers (such as Mexico) or exclusively exporters (such as China). The authors conclude that this study opens the door to more efficient hazardous waste management and allows the implementation of measures to ensure better control of hazardous waste.Johann H. Martínez, Sergi Romero, José J. Ramasco, and Ernesto Estrada. The world-wide waste web. Nat. Comm. DOI: 10.1038/s41467-022-28810-xCSICAgencia SINC http://ifisc.uib-csic.es/en/news/world-wide-waste-web-network-through-which…

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IFISC News - IFISC Poster Party 2022
by ifisc＠ifisc.uib-csic.es 22 Mar '22

22 Mar '22

IFISC Poster Party 2022 The IFISC Poster Party is an annual activity where PhD students and postdoctoral researchers of IFISC present their research in a poster format. In a relaxed atmosphere, you can get to know first-hand what the young researchers a IFISC are working on. This year, again due to health restrictions for the Covid-19 pandemic, the Poster Party changes its format. For one whole week (until March 25), the posters of the participants will be hung in the IFISC hallways as usual, but an online modality will be added: the posters will be also available for viewing through this page. To replace the explanations of the authors themselves, each of them has prepared a short video explaining the research carried out and the conclusions of the study. Questions to the authors could be done personally in their offices/desks or via email. Voting for the best poster in each category will be done through an online form that will remain open until March 25 at noon. IFISC Poster Week 2022 http://ifisc.uib-csic.es/en/news/ifisc-poster-party-2022/

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IFISC News - Voces, CSIC Balears: Quantum physics, thermoelectricity and nanoconductors
by ifisc＠ifisc.uib-csic.es 09 Mar '22

09 Mar '22

Voces, CSIC Balears: Quantum physics, thermoelectricity and nanoconductors IFISC (UIB-CSIC) and the Institutional Representation of CSIC in the Balearic Islands join forces and create "Voces, CSIC Balears", a bimonthly podcast for the dissemination of science. Through interviews with scientists working at CSIC's centres in the Balearic Islands (IMEDEA CSIC-UIB, IFISC UIB-CSIC and ICTS SOCIB), it aims to increase the visibility of the science carried out in the region. The 20th episode of "Voices, CSIC Balears" features Rosa López. Rosa has a degree in theoretical physics from the Autonomous University of Madrid and a PhD in physics from the Institute of Materials Science of Madrid. Rosa is currently a professor in the Department of Physics at the University of the Balearic Islands and a permanent researcher at IFISC. She is part of three research projects related to quantum transport and topological materials: QTEP, MACTOPE and QuTTNAQMa. Física cuántica, termoelectricidad y nanoconductores | VOCES, CSIC BALEARS #20 http://ifisc.uib-csic.es/en/news/voces-csic-balears-quantum-physics-thermoe…

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IFISC News - Summer Undergraduate Research Fellowships SURF@IFISC 2022
by ifisc＠ifisc.uib-csic.es 22 Feb '22

22 Feb '22

Summer Undergraduate Research Fellowships SURF@IFISC 2022 The Institute for Cross-Disciplinary Physics and Complex Systems (IFISC, UIB-CSIC) announces the 2022 SURF@IFISC (Summer Undergraduate Research Fellowships) program, addressed to undergraduate students interested in having a first contact with scientific research in the field of Complex Systems. These scholarships, awarded since 2013, aim at introducing student fellows to cutting-edge research and complete their training with practical applications of their knowledge. 6 projects are offered in one of the leading research centers on Complex Systems worldwide. The fellowships must be carried out between June 27th and July 29th for about 150 hours. The research work will take place at the IFISC institute under the supervision of a faculty member. Internships have assigned a total research work of 150 hours, equivalent to four weeks working full time. Each fellowship provides 500 Euros for students living in Mallorca and 800 Euros for a 30-day stay otherwise. The minimum requirements comprise at least 120 ECTS credits of an official degree with an averaged qualification equal or greater than 7/10. The application deadline is April 24th, 2022. More details can be found at the SURF@IFISC page, where the online application form can be found. http://ifisc.uib-csic.es/en/news/summer-undergraduate-research-fellowships-…

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IFISC News - IOP-IFISC Webinar on ‘Complex Systems Approaches to Information Processing’
by ifisc＠ifisc.uib-csic.es 11 Feb '22

11 Feb '22

IOP-IFISC Webinar on ‘Complex Systems Approaches to Information Processing’ IFISC together with the Institute of Physics (IOP), organize a webinar about Complex Systems Approaches to Information Processing presenting a recent special issue in J. Phys. Complexity edited by Maxi San Miguel, Claudio Mirasso and Ingo Fischer. The general topic of the webinar is the subject of the research program of IFISC´s Maria de Maeztu Unit of Excellence. The webinar (March 8, 3pm CET) will include a round table discussion on this topic. The area of information processing and computing is highly fractionalized. It covers sub-fields in machine learning, neuroscience, physics, mathematics, computer science, engineering, biology, social sciences, and more. Not only digital computers, but also organisms, brains, nonlinear physical, quantum, and socio-technical systems, as well as artificial neural networks and many other complex systems, carry out complex information processing. How systems process, store, and retrieve information, and how they can even learn to improve on specific tasks as an interplay of structure and dynamics are fundamental questions at the core of research in complex systems that we need to answer. Finding answers will represent the basis to a better understanding, and ultimately to designing efficient and robust complex information processing systems. This free webinar brings together five different perspectives from this endeavor and aims to explore the role that complex systems science plays in connecting the various involved fields. Speakers Karoline Wiesner: Professor of Complexity Science, Department of Physics and Astronomy, University of Potsdam, Germany Hiba Sheheitli: Postdoctoral Researcher, Institut de Neurosciences des Systèmes, Inserm and Aix-Marseille University, FranceMarc Timme: Chair for Network Dynamics, Center for Advancing Electronics Dresden (CFAED), TU Dresden, Germany Daniel Gauthier: Professor of Physics at The Ohio State University, USA Roberta Zambrini: Tenured researcher of the Spanish national research council (CSIC) at IFISC (UIB-CSIC), SpainAttendance to the webinar requires registration in advance: https://register.gotowebinar.com/register/8529868692589874188 http://ifisc.uib-csic.es/en/news/iop-ifisc-webinar-complex-systems-approach…

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IFISC News - 11F: International Day of Women and Girls in Science 2022. Towards a Gender Equity plan at IFISC
by ifisc＠ifisc.uib-csic.es 11 Feb '22

11 Feb '22

11F: International Day of Women and Girls in Science 2022. Towards a Gender Equity plan at IFISC In 2015 the United Nations General Assembly decided to proclaim 11 February as International Women's and Girls' Day in Science with the goal of achieving full and equal access to science for girls and women. At IFISC, a team of students, postdocs, permanent researchers, administration personnel and technicians, has started to work on an IFISC gender equity plan. To this end, a survey has been distributed to all IFISC members in order to gather opinions, experiences and suggestions that can help in the preparation of the plan. The infographic that accompanies this News article summarizes the main findings of the survey, where the anonymity of all answers has been guaranteed and no demographic information has been requested except for gender. A 92% of the inquired people support this initiative. The survey provides a good measure of the state of gender-related aspects at the present time and to identify pressing issues before the preparation of the IFISC gender equity plan. By comparing the responses to current and future surveys, one can monitor if the actions that will be included in the equity plan have any measurable consequences. The survey has been prepared inspired by the Gender Equality in Academia and Research (GEAR) tool, which provides universities and research organisations with practical advice and tools. The equity team at IFISC is committed to implement measures to improve the working conditions of all IFISC personnel, with special attention to underrepresented groups. The answers to the survey indicate that there is a clear need to raise awareness about equity issues across the institute. IFISC presents these results within the 11F 2022 program organized by the 11F Balears Platform, whose objective is to give a face and a voice to women who, from institutions, companies or individually, develop their professional and academic activity especially in the field of the STEM sectors. The complete list of activities that will be organized in the framework of the 11F can be found in the web 11fbalears.org. http://ifisc.uib-csic.es/en/news/11f-international-day-women-and-girls-scie…

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IFISC News - IFISC People: Esteve Seguí
by ifisc＠ifisc.uib-csic.es 28 Jan '22

28 Jan '22

IFISC People: Esteve Seguí We are pleased to introduce Esteve Seguí to the other IFISC members. Esteve has a degree in web development, having done an internship at APSL. He is also a qualified microcomputer and network technician, with an internship at BEL Informática, and holds certifications in programming and computer security. He has carried out several programming projects with different languages available in his portfolio. At IFISC he will work as web developer in charge of the maintenance and management of the institute's multiple web services. http://ifisc.uib-csic.es/en/news/ifisc-people-esteve-segui/

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IFISC News - The shape of memory in temporal networks
by ifisc＠ifisc.uib-csic.es 25 Jan '22

25 Jan '22

The shape of memory in temporal networks An international team of researchers, with participation of IFISC (UIB-CSIC), have proposed a mathematical framework to estimate the memory structure of temporal networks. These findings are published in the latest issue Nature Communications.Temporal Networks (those whose structure changes over time) are a very useful tool for studying complex systems. But the properties of a temporal network not only depend on the patterns of activities of each of its links, but also on the ways in which these activities influence each other across the network. This rich dynamic gives rise to the notion of network memory, this is, the dependence of a temporal network’s structure on its past.To this objective, an interdisciplinary and international team of researchers, with the participation of IFISC (UIB-CSIC), have proposed a mathematical framework to unveil the microscopic structure of a network’s memory. Their results suggest that, contrary to previously assumed, it is not possible to reduce the structure of such memory to a number: memory is inherently high-dimensional, it is not just one number, it is more like a shape. As Richard Feynman famously said, “there is more room at the bottom”, and this is true for network’s memory. Furthermore, they showed that inside such memory shape, weird things happen. Like the emergence of so-called virtual loops, consisting in resonance effects that happen when the future of a link depends on the past of a second link whose future, in turn, depends on the past of the first one. While a priori only a mathematical curiosity, it turns out that these virtual loops are physically felt by the system: the outcome of an epidemic process running on top of a network is very different if virtual loops emerge.The researchers applied this framework to characterize the memory of a large number of real-world networks, including urban transport networks in European cities (such as bus, train or metro), cortical brain networks, communication networks (SMS or email) and even contact networks between university students. Studying these systems, they found, among other results, that network memory is much higher in offline networks. In other words, a current state has a greater capacity to affect future configurations since offline social interactions are more mediated by tight schedules, which facilitate the emergence of various orders of memory. The analysis of real-world temporal networks also revealed that there are asymmetries in the contribution of links to the evolution of the network in terms of followers/influencers. All together provides evidence that memory shapes can very heterogeneous in real-world systems. The manuscript also provides implementations of the algorithms proposed hoping that their framework will prompt further studies and applications in other areas of complex systems. Williams, O.E., Lacasa, L., Millán, A.P. et al. The shape of memory in temporal networks. Nat Commun 13, 499 (2022). Doi: https://doi.org/10.1038/s41467-022-28123-z http://ifisc.uib-csic.es/en/news/shape-memory-temporal-networks/

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