Search results for "ERC"

Flat-band superconductivity in strained Dirac materials

2016

We consider superconducting properties of a two-dimensional Dirac material such as graphene under strain that produces a flat band spectrum in the normal state. We show that in the superconducting state, such a model results in a highly increased critical temperature compared to the case without the strain, inhomogenous order parameter with two-peak shaped local density of states and yet a large and almost uniform and isotropic supercurrent. This model could be realized in strained graphene or ultracold atom systems and could be responsible for unusually strong superconductivity observed in some graphite interfaces and certain IV-VI semiconductor heterostructures.

Two-dimensional materials: from hybrid magnetic multilayers to superconducting single layers

2013

El trabajo descrito en esta tesis se encuadra en el ámbito de los materiales laminares con propiedades magnéticas de interés empleados como sistemas químicamente versátiles. En cuanto a su versatilidad química, los materiales laminares constituyen un ejemplo clásico de lo que se denomina una estructura anfitrión, capaz de albergar por intercalación otras especies químicas en su interior de forma mas o menos ordenada. Dos son las familias de compuestos estudiadas en este trabajo: los hidróxidos dobles laminares (layered double hydroxides, LDHs) que exhiben un comportamiento magnético químicamente modulable y los dicalcogenuros de los metales de transición (transition metals dichalcogenides, …

Magnetic Field Dependence of Microwave Surface Resistance in MgB2

2008

Superconductivity explained with the tools of the classical electromagnetism. Educational path for secondary school and its experimentation.

2014

The work of this thesis describes an educational path for the presentation of superconductivity at the secondary school, together with the experimentation of some particular parts of the path with high school students. The educational path that we have developed is mainly centred on the phenomenological aspects of superconductivity and has been inspired by the two fluid theory of Gorter and Casimir (1934) where a superconductor is seen as a material in which two fluids are present, the normal fluid described by the Ohm's laws, and the superconductive fluid descibed by the London equation (1935). Both the Ohm's laws and the London equation give respectively the phenomenological descriptions …

Quantum fluctuations in superconducting nanostructures

2014

Modern nanofabrication technology enableTfabrication of very narrow quasi-1-dimensional superconducting nanowires demonstrating finite resistivity within the range of experimentally obtainable temperatures. The observations were reported in ∼10 nm nanowires of certain superconducting materials. The effect has been associated with quantum phase slip process - the particular manifestation of quantum fluctuations of the order p arameter. In titanium, the phenomenon can be observed already at dimensions ∼35 nm where the fabrication is well reproducible and the dimensions of samples can be characterized with high accuracy. We have performed systematic study of the size dependence of transport pr…

Dipendenza dal campo magnetico della resistenza superficiale a microonde in MgB2

2008

A one-pot method to enhance dissolution rate of low solubility drug molecules using dispersion polymerization in supercritical carbon dioxide

2009

Preparation of pH sensitive poly(vinilydenefluoride) porous membranes by grafting of acrylic acid assisted by supercritical carbon dioxide

2010

Aim of this work is to study the preparation of pH sensitive membranes for biomedical applications via thermal induced graft polymerization of acrylic acid (AA) on poly(vinilydenefluoride) (PVDF) assisted by supercritical carbon dioxide (scCO2). Using scCO2 as a solvent and swelling agent, the monomer and initiator (benzoyl peroxide) could diffuse faster and distribute more uniformly into the polymer matrix. A better control of the final molecular architecture should be achieved because bimolecular grafting reactions are accelerated with respect to chain degradation processes. Commercial hydrophobic PVDF porous matrixes were selected as model membranes. Grafted polymers were characterized b…

Melt phase ring opening polymrization of lactide and glycolide assisted by supercritical carbon dioxide

2010

Supercritical carbon dioxide induces sterilization of PLLA scaffolds contaminated by E. coli.

2014

The common sterilization techniques are based on physical processes that involve, for example, the use of autoclaves or systems to radiation such as γ-rays that can cause a structural change of the polymer treated. Therefore, the use of supercritical carbon dioxide (scCO2) is an excellent alternative, as it does not induce any variation of biomaterials treated (Perrut M., 2012). It's a good candidate because is readily available at low cost, non-toxic and non-flammable, it has an easily accessible critical point (7.38 MPa and 304.2 K) and excellent transport properties and wettability (White A. et al., 2005). We report the development of a supercritical CO2 based process capable of steriliz…