RESEARCH GROUPS
Although independent research groups remain, the Centre operates as a transversal, challenge-oriented research ecosystem, promoting flexible collaborations and project-driven approaches that integrate expertise across traditional disciplinary boundaries, defined by the five research lines and transversely crossed by the two axis of societal domains.
GAS/SOLID INTERFACES
The “Gas/Solid Interfaces” group focuses on the atomic-level understanding of physical and chemical processes arising at the interface between gas and solid phases of matter. The understanding of these elementary reactive and non-reactive processes is crucial in many energy- and environmental-related applications, including heterogeneous catalysis, electrochemistry, hydrogen storage, and fusion reactors. The activity of the “Gas/Solid Interfaces” group relies on the development of new methodologies as well as on the use of first-principles electronic structure calculations to describe the interaction dynamics in such complex systems. Particular attention is paid to the development of theoretical models able to describe the non-adiabatic contributions and the energy dissipation channels that come into play, because they can drastically change the output of the dynamics. Current research in the group also includes methodological advance in the simulation and analysis of photo-induced adsorbate dynamics and reactions, as well as the use of machine learning strategies specifically adapted to study the gas/solid interface dynamics.
QUANTUM PHENOMENA ON SURFACES
The activity of the Quantum Phenomena on Surfaces group focuses on the development of computational schemes to unveil the richness of realistic spectral functions, with Dr. Deung-Jang Choi leading the experimental work and Dr. Nicolas Lorente leading the theoretical work. The main research topics in the group are electronic, vibrational and magnetic excitations, particularly of molecular and nanomagnetic systems on solid surfaces, ranging from semiconductors and metals to superconductors. In recent years, the following objectives have been addressed on these topics: (i) the use of density functional theory to understand the geometrical and electronic structure of different surface systems, and (ii) the development of theories and numerical treatments to understand phenomena revealed by STM.
NANOPHYSICS LABORATORY
The NanoPhysics Lab (NPL) group studies structural, electronic, magnetic and chemical properties of in-si- tu and ex-situ grown nanostructures in the context of experimental surface science. NPL aims at exploring relevant but yet-widely-unknown phenomena taking place at the surface of solid materials, such as the ato- mic-level control of on-surface chemical reactions and catalysis, the bottom-up fabrication of 1D or 2D func- tional materials, and also the growth of novel layered materials with potential application in state-of-the-art technology devices. The group applies the synthesis of atomically perfect materials to practical problems of technological and industrial interest, aligned with three current social challenges: quantum technologies, mo- lecular precision chemical sensors, and catalysts for green energies.
The NPL holds some of the most complete and modern set of highly sensitive surface science techniques, combined with the tools for the growth of materials and nanostructures, from layer-by-layer growth to device fabrication. Thus, NPL laboratory has several multi-technique ultra-vacuum equipment distributed in flve different laboratory rooms.
MODELISATION AND SIMULATION
The activity of the “Modelisation and Simulation” group focuses on the theoretical study of the electronic and structural properties of complex materials, clean and decorated surfaces, and nanostructures. It pursues the following objectives: (i) to develop the basic theory and ab-initio simulation tools in order to study the behavior of different nanoelectronic devices, particularly those based on graphene derivatives, (ii) to study the optical properties of complex organic/inorganic interfaces, (iii) to study the magnetic properties of different nanostructures, ranging from one dimensional systems to coordination networks and multilayer heterostructures at surfaces, and (iv) to continue to foster the development of the SIESTA code. Most of the research activity of this group is performed in close collaboration with other experimental and theoretical groups at CFM, and also with groups from other research centers in the Basque Country.
SPECTROSCOPY AT THE ATOMIC SCALE
The activity of the Spectroscopy at Atomic Scale group is devoted to explore the structural and spectroscopic characteristics of materials at the local scale, with the use of Scanning Tunneling Microscopy (STM) techni- ques. The objectives of this activity focus on: (i) the understanding of different mechanisms that influence the electronic, magnetic and vibrational properties on surfaces, (ii) the study of electron transport and che- mical reactivity of surface supported nanostructures, (iii) the investigation of new strategies leading to the formation of covalently bonded conjugated structures with functional groups, and (iv) two dimensional pro- perties emerging in layered materials.
The experimental research activity is based on a low temperature scanning probes microscope, which is used to correlate structure, electronic and vibrational properties of nanostructures and interfaces at the ato- mic scale. The growth of the interfaces as well as their characterization take place in ultra-high vacuum and at temperatures down to 1K, a challenging situation from the methodological point of view.
Electronic Excitations in Surfaces and Nanostructures
The activity of the Electronic Excitations in Surfaces and Nanostructures group is devoted to the theoreti- cal study of electronic and magnetic properties of so- lids, surfaces and low-dimensional systems, focusing particularly on systems of nanometer size. The general interests of this activity include: (i) spin dependent electronic excitations in oxides and metals, (ii) electro- nic states and excitations in topological insulators, (iii) many-body theory of electron lifetimes, (iv) basic pro- perties, such as energy dispersion and lifetimes of no- vel low-energy collective excitations, and (v) studies of nanostructures, such as two-dimensional graphene-li- ke materials, and inorganic nanotubes and minerals containing silicate chains.
In recent years, electronic and magnetic properties of materials have been investigated by this group using fl principles methodologies. Electron dynamics in different systems have been also studied, with particular empha- sis on ultrafast processes and size effects. Advanced materials, such as topological insulators and cement-re- lated systems, are current targets of these activities.
Quantum Theory of Materials
The activity of the “Quantum Theory of Materials” group focuses on the first-principles calculation of materials properties and the development of new ab initio techniques. The group develops new theoretical methods to overcome the problems associated to standard theoretical approaches, specially, to describe with improved accuracy the quantum description of the electron-phonon and phonon-phonon interactions. These new techniques are applied to understand the electronic and vibrational properties of complex materials as well as to predict new compounds with interesting properties fully ab initio.
In the last years, the team has concentrated its efforts to study (i) high-temperature superconducting hydrogen-based compounds at high pressure, as well as hydrogen itself; (ii) thermoelectric and charge-density wave materials both in the bulk and the monolayer, aiming at characterizing their phase diagram and their transport properties; (iii) collective electronic excitations in metals; (iv) phonon polaritons; (v) optical lattices; and, finally, (vi) biophysical systems.
Aitor Bergara, associate professor at UPV/EHU, Jose María Pitarke, director of CIC nanoGUNE and university professor at UPV/EHU, and Ion Errea, associate professor at UPV/EHU, share interests and work as permanent researchers in this group, currently lead by Ion Errea. The later has gathered a team settled at CFM headquarters, constituting the new “Errea Lab”.
MESOSCOPIC PHYSICS
The Mesoscopic Physics group activity focuses on the theoretical aspects of quantum transport in nanostructures and mesoscopic systems. The main research covers various materials and structures, including metals, ferromagnets, semiconductors, superconductors, low dimensional systems, and topological matter. In addition to the theoretical activity, the group has a large network of experimental collaborators.
In the past years, particular emphasis is placed on the following research objectives: (i) to develop theoretical tools for studying spin-dependent transport in hybrid systems with spin-orbit coupling, exchange flelds, and superconductivity; (ii) to analyze the electronic heat transport at the nanoscale; (ii) to explore the possibility of using superconducting materials for sensing and detection; and (iv) to design electronic and spintronics devices with new functionalities.
NANO-BIO SPECTROSCOPY
“Nano-bio Spectroscopy” group focuses on the theory and modelling of electronic and structural properties in condensed matter and on developing novel theoretical tools and computational codes to investigate the electronic response of solids and nanostructures to external electromagnetic fields. Present research activities include new developments within many-body theory and TDDFT. The theoretical description of optical spectroscopy, time-resolved spectroscopies, STM/STS and XAFS is also addressed. Methodological developments include novel techniques to calculate total energies and assessment and development of exchange-correlation functionals for TDDFT calculations and improvements on transport theory within the real-time TDDFT formalism.
SOUZA GROUP
The activity of this group focuses on fundamental condensed-matter theory, using computational techniques to study the properties of advanced materials from first principles. The activities that the group continues to pursue are: (i) the study of the ground-state, optical, and transport phenomena that arise from broken symmetries, such as time reversal (magnetic order) and spatial inversion, and (ii) the description of electronic properties of solids by using geometric phases and related concepts.
In recent years, the work has involved the development of new theoretical approaches and algorithms, and their application to problems of current interest, including methods to study insulators infinite electric fields, as well as to construct localized Wannier orbitals for metals. Phenomena that arise from the interplay between the collective magnetic order in solids and the spin-orbit interaction inside the constituent atoms have been also successfully addressed.
CERAMIC AND CEMENT-BASED MATERIALS
The group researches a variety of properties of cement-based and ceramic materials experimentally and theoretically. Combining knowledge from different disciplines, like solid-state physics, soft-matter physics, geochemistry and chemical engineering, the “Ceramic and Cement-based Materials” group focuses on the computational design and synthesis of new ceramic and cement-based materials with lower CO2 flngerprint.
The initial objectives of the group are: (i) the use of atomistic and colloidal simulations to study the structure and properties of cement-based materials, (ii) the implementation of new technologies in hydrothermal and supercritical fluids (SCF) for the ultra-fast synthesis of ceramic nanoparticles, (iii) the development of new sintering methodologies through the use of autoclaves or microwaves that allow notable energy savings and a drastic reduction of CO2 emissions, and (iv) the development of energy storage solutions derived from cement-based materials, including both chemical storage (batteries) and thermal storage systems (TES) applications
THEORY OF ELECTRONIC AND OPTICAL EXCITATIONS IN SOLIDS
The group’s research focuses on material properties of current interest, including (but not limited to) nonlinear optical response of semiconductors, collective electronic excitations, and magnetic behavior of low-dimensional systems like single adatoms. For the first-principles characterization of these systems we generally make use of state-of-the-art software packages that implement the density functional theory. For the analysis of the more exotic properties we develop our own algorithms and theoretical approaches, which often make use of k-dot-p and tight-binding models.
THEORY OF NANOPHOTONICS
The activity of the “Theory of Nanophotonics” group is devoted to the theoretical study of the interaction between electromagnetic radiation and nanostructured materials. The research activity of the group focuses on the theoretical study of the excitation of plasmons, quantum dots and dielectric nanostructures in the context of a variety of microscopy and spectroscopy configurations: Dark Field Microscopy (DFM), scattering-type Scanning Near-Field Optical Microscopy (s-SNOM), Electron Energy Loss Spectroscopy (EELS), Scanning Tunneling Microscopy (STM), Surface-Enhanced Raman Scattering (SERS), Surface-Enhanced Infrared Absorption (SEIRA) and Surface-Enhanced Fluorescence (SEF), among others.
In recent years, the following specific objectives have been addressed by this group: (i) understanding and characterization of the collective excitations of the electron gas, plasmons, in a variety of spectroscopy and microscopy techniques, (ii) study of metallic nanostructures as electromagnetic field enhancers and localizers, (iii) development of protocols and models to better interpret and describe the images obtained by the scattering-type near-field optical microscope, (iv) study and exploitation of the interaction of fast electrons and matter to develop new paradigms of spectroscopy in the nanoscale, (v) description of quantum effects derived from the coherent nature of the electrons that constitute a plasmonic excitation, (vi) study of the magnetic activity of dielectric nanostructures at optical frequencies, (vii) characterization of the dynamics and the coupling of emitters to be used in quantum information technology, and (viii) address non-linearities and collective effects in molecular optomechanics.
NANOMATERIALS AND SPECTROSCOPY
The activity of the Nanomaterials and Spectroscopy group focuses on the experimental study of spectroscopy and photonic applications of nanoscale functional units, including semiconductor quantum dots and quantum wires, metal nanoparticles and nanoantennas, as well as organic/inorganic nano-hybrid systems. A nanophotonics laboratory, where lifetime microscopy based on fluorescence emission spectroscopy is the fundamental equipment, allows this activity.
Over the past years, the research on this topic has target- ed the following specifl objectives: (i) the development of novel nano-hybrid materials using nanoscale building blocks, (ii) the investigation of the interaction between light and nanoscale systems, (iii) the experimental study of the energy transfer and conversion in nanostructures down to single quantum dot / molecule level, and (iv) the development of novel experimental approaches to con- trol, manipulate and probe with light on nanoscale.
Laser Physics and Photonic Materials
The activity of the Laser Physics and Photonic Mate- rials group concentrates most of the research efforts on the study of light-matter interaction processes in new photonic materials with potential applications in the fl of optoelectronics (light amplifl lasers, light converters, laser coolers…) and biomedicine (nanostruc- tured optical tracers, multispectral 3D images, sensors).
In recent years, the following specifl objectives have been pursued on this topic: (i) the investigation on rare earth-doped vitroceramics for integrated optics applications, (ii) the study of the laser emission processes in dye-doped micro-nano structured hybrid materials for optoelectronic and biomedical applications, (iii) the syn- thesis and development of new eutectic materials for biomedical applications, (iv) the experimental and theoretical study of light generation in rare-earth doped micro-nanocrystalline dielectric powders for infrared random lasers, (v) the study of laser-induced refrigeration in rare earth-doped micro-nano structured materials, and (vi) the design and making up of an optical wave guide writing system by using a femtosecond laser.
QUANTUM NANOPHOTONICS LABORATORY
The Quantum Nanophotonics Laboratory is composed by a team of scientists endeavoring to unveil the physics of the interactions of quantum light and matter at the nanoscale. The group experiments with exotic states of light such as single photon states, entangled photons or squeezed states of light, and forces them to interact with very small structures, aiming to control the quantum features of nanoparticles by exploiting their interaction with light. This allows to design more precise quantum enhanced sensors, improve information processing and above all, pierce through the frontiers of knowledge and excite our curiosity.
Created in early 2018 and since then has expanded to encompass a series of experimental techniques, including optical spectroscopy with classical and quantum light, development of quantum sources of light, quantum control of nanostructures, optical tweezers and optical levitation.
Currently, the laboratory hosts three optical tables, an optically addressable closed-cycle cryostat, a set of tunable laser sources, and an optical tweezers platform, among other optical equipment.
POLYMERS AND SOFT MATTER
The general scientific objective of the activity program of this group is to achieve a fundamental understanding of the interplay between structure and dynamics at different length and time scales (micro, nano, meso, macro) in materials of increasing complexity based on polymers, glass-forming liquids and soft matter, in particular: polymers with different architectures, single-chain polymer nano-particles, multi-component, nano-structured and biopolymer systems. These materials exhibit complex dynamics and rheology and, in many cases, show hierarchical relaxations over many different length- and time-scales, which need to be unravelled. This in turn affects the processing and properties of the final materials. In order to rationally design appropriate materials and processes for various technological applications, a rigorous knowledge of the interplay between structure and dynamics at different length and time scales is demanded.
Taking inspirations from classical polymer physics, soft matter physics and the physics of condensed matter, the Polymers and Soft Matter group has developed over last years a robust and pioneering methodology to carry on this program. This methodology is based on the combination of different experimental relaxation techniques with neutron, XR and light scattering methods, molecular dynamics simulations and chemical synthesis oriented to polymers. The organization of the group is in fact driven by this methodology and the staff of the group (scientists belonging to the CSIC, the UPV/EHU and Ikerbasque) is composed by experts in different techniques/methods, all of them being involved in the scientific objectives defined at any time.
QUANTUM BEAMS AND COMPUTATION FOR SUSTAINABLE MATERIALS
The “Quantum Beams and Computation for Sustainable Materials” group uses an multi-pronged approach involving quantum beams, theory and simulation to interrogate and understand the structure and properties of sustainable novel functional materials for energy applications, nanoelectronics and lighting.