Dielectric-permittivity-driven charge carrier modulation at oxide interfaces

High-quality bilayers of La-doped SrTiO3 (STO) and LaAlO3 (LAO) on SrTiO3 have been grown controlling the location and behavior of the charge carriers by changing the thicknesses of the layers, which are dielectrically mismatched. In this system, the charge carriers are created at the La:SrTiO3/LAO interface and spread out toward the substrate due to the increase in dielectric constant as the temperature is lowered. When the electrons reach the interface of the La:SrTiO3 and the pure STO, they display enhanced mobility in the quantum well at that interface for specific thicknesses

Un capítulo recuperado en la historia de la Universidad de Barcelona: el programa de cursos para el año 1936-1937

Podeu consultar el document original sobre el que es basa el treball en català a: http://hdl.handle.net/2445/33756 i en castellà a: http://hdl.handle.net/2445/33755Afortunadamente, en los últimos años la bibliografia sobre la historia de la Universidad de Barcelona (y en especial del periodo de la autonomía universitaria, la guerra civil y la posguerra) se ha ido enriqueciendo con importantes aportaciones, cubriendo asi un área fundamental para comprender nuestro presente y poder encarar mejor nuestro futuro. Estos estudios establecen análisis de conjunto absolutamente necesarios para empezar a desbrozar el terreno, pero son necesarias también investigaciones parciales, más concretas, que vayan arrojando luz sobre aspectos poco conocidos o que todavía permanecen por estudiar en nuestros archivos

An Epitaxial Transparent Conducting Perovskite Oxide: Double-Doped SrTiO3\ud

Epitaxial thin films of strontium titanate doped with different concentrations of lanthanum and oxygen vacancies were grown on LSAT substrates by pulsed laser deposition technique. Films grown with 5−15% La doping and a critical growth pressure of 1−10 mTorr showed high transparency (>70−95%) in the UV−visible range with a sheet resistance of 300−1000 Ω/. With the aid of UV−visible spectroscopy and photoluminescence, we establish the presence of oxygen vacancies and the possible band structure, which is crucial for the transparent conducting nature of these films. This demonstration will enable development of various epitaxial oxide heterostructures for both realizing opto-electronic devices and understanding their intrinsic optical propertie

An epitaxial transparent conducting perovskite oxide: double-doped SrTiO3

Epitaxial thin films of strontium titanate doped with different concentrations of lanthanum and oxygen vacancies were grown on LSAT substrates by pulsed laser deposition technique. Films grown with 5−15% La doping and a critical growth pressure of 1−10 mTorr showed high transparency (>70−95%) in the UV−visible range with a sheet resistance of 300−1000 Ω/. With the aid of UV−visible spectroscopy and photoluminescence, we establish the presence of oxygen vacancies and the possible band structure, which is crucial for the transparent conducting nature of these films. This demonstration will enable development of various epitaxial oxide heterostructures for both realizing opto-electronic devices and understanding their intrinsic optical propertie

How Persuasive is a Virtual Coach in Terms of Promoting Web-based Intervention User Engagement?: Exploring a Potential Match between User Support Needs and a Virtual Coach’s Motivational Capabilities

A selection of web-based eHealth interventions have evolved from innovative prototypes to evidence-based and clinically applied solutions for mental diseases such as depression and anxiety. Open-access, self-guided types of those solutions hold the promise of reaching and treating a large population against reasonable costs. However, a considerable factor that currently hinders the effectiveness of these self-guided web-based interventions is the high level of attrition. The absence of a human caregiver apparently has a negative effect on user adherence. Although clear evidence on the rationale for non-adherence is currently missing, recent studies indicate that user support could an important causal factor. In this paper we describe the protocol of an exploratory user study which aims to identify the persuasive features of virtual coaches in terms of user support. Virtual coaches are anthropomorphized instances of software, designed to engage and motivate users. We will measure user experience, engagement, motivation and perceived persuasiveness during usage of the ‘Living to the Full’ intervention. We will compare a condition with and without empathic virtual coach condition to explore its supportive capabilities

A Scoped Review of the Potential for Supportive Virtual Coaches as Adjuncts to Self-guided Web-Based Interventions

This study aimed to explore supportive capabilities of VAs with the potential benefit in mind that users of self-guided eHealth interventions could be better supported. Spontaneous empathy and the explicitly expressed intention of non-responsive VAs to deliver user support is likely capable to engage and motivate users. Responsive VAs have even larger potential. However, they are more costly to realize and have a higher risk of failure. Effective user frustration detection and mitigation by Responsive VAs has been empirically demonstrated, but so far within artificial contexts. Altogether it makes sense to further explore the option to add VAs as adjuncts to self-guided eHealth interventions a potential remedy to low adherence