Research projects offered as TFG in Physics (Degree in Physics at UAB) 2017

1.- Photoresponse of non-centrosymmetric materials

Supervisors: Josep Fontcuberta & Ignasi Fina

 

Brief description of the objectives

Non-centrosymmetric materials have unique properties that could be of the highest interest for efficient photovoltaic energy conversion. The aim of the proposed TFG is that the student get used with the concepts involved in the photoresponse of non-centro-symmetric materials and the methods to study and understand it.

 

Brief description of the methodology

The project will include the electric characterization of ferroelectric and other polar materials (mainly thin films only few tens of nanometer thick) and their photoresponse. The samples will be illuminated with light of various wavelengths and polarization and the photoresponse will be determined. The candidate will participate to the weekly meetings of our research group, learning how to present and discus experimental results.

 

2.- Using light to study new materials for electronics

Supervisors: Gervasi Herranz

 

Brief description of the objectives

In our lab we are investigating new materials for applications in information technologies. One of our research lines aims at modulating the information stored in magnetic moments by the application of electric field pulses that, in turn, generate strain waves that stretch/squeeze locally the ferromagnet and change its magnetic state. We study these phenomena optically: the student will be trained in optical imaging and spectroscopy.

 

Brief description of the methodology

The candidate will have access to our advanced optical laboratory, which includes optical spectroscopy and high-resolution imaging tools. The candidate will follow an intensive training, so as to ensure a solid understanding of the techniques. The student will be acquainted with state-of-the art techniques that allow real-space mapping of optical responses with diffraction limitation That allows the visualization of features below the micron down to just a few of hundreds of nanometers, enabling direct imaging of small devices and high sensitivity to magnetic fields. The optical lab at ICMAB is suited to visualize plasmon propagation in real space as well as in reciprocal space, i.e., plasmonic and photonic band dispersions can be obtained from throughout near-IR to near-UV frequencies.

 

 

 

MASTER PROJECTS (CLOSED)

Notes

  • Projects are intended for MASTER students on Material’s Science, Condensed Matter, Solid State Physics, Crystallography, Advanced Microscopies, etc.
  • The projects are expected to have a duration of about 6 months.
  • Research activity costs are covered by running projects.
  • No grants or other financial support can be provided

 

Description and Contacts

 

Magneto-Optical Spectroscopy of Nanostructured Magnetic Materials

Magneto-optical materials are nowadays intensively researched because of potential applications in optical communications or data storage. An important aspect of this research field is to understand how their properties evolve with the wavelength of the probe light. The student will be trained on using magneto-optical spectroscopy to analyze the properties of nanostructured magnetic materials as well as nanometer-thick magnetic films as a function of the light frequency.

 

Interested candidates should contact:

Gervasi Herranz and D. Pesquera

Institut de Ciència de Materials de Barcelona ICMAB-CSIC
Campus de la UAB,
08193 Bellaterra, Spain
gherranz@icmab.es
Phone: +34 93 580 18 53

 

Imaging ferromagnetic and ferroelectric domains with submicron resolution

The data in electronic devices can be stored permanently in magnetic or ferroelectric domains. A direct visualization of these domains is a prerequisite to understand the evolution of their spatial distribution under the application of external fields (magnetic or electric). The candidate will contribute to develop and make use of advanced optical microscopy (confocal) with polarization contrast to image ferromagnetic and ferroelectric domains of thin film structures as well as nano-objects with a lateral resolution well below the micrometer. The project will allow the candidate to obtain formation on modern optical microscopy techniques.

 

Interested candidates should contact:

Gervasi Herranz and Ondřej Vlašín

Institut de Ciència de Materials de Barcelona ICMAB-CSIC
Campus de la UAB,
08193 Bellaterra, Spain
gherranz@icmab.es
Phone: +34 93 580 18 53

 

Nanometric Magnetic Tunnel Heteroepitaxies

Spintronics is one of the most advanced technologies to overcome present limitations of conventional electronics. Magnetic materials are at the heart of spintronics and progress requires development of new materials and concepts. We are currently developping spin filters. We offer to contribute to the ongoing research. The student will be trained on using Pulsed laser deposition and sputtering techniques to grown epitaxial layers of oxides and metals. This activity will be combined with advanced structural characterization and atomic-force miscroscopies.

 

Interested candidates should contact:

Josep Fontcuberta

Institut de Ciència de Materials de Barcelona ICMAB-CSIC
Campus de la UAB,
08193 Bellaterra, Spain
fontcuberta@icmab.es Phone: +34 93 580 18 53 (228)

 

 

Oxide superlattices by pulsed laser deposition with reflection high energy electron diffraction

New artificial materials can be created by exploiting properties derived of interfaces between two materials. Superlattices, i.e., thin films multilayers type A/B/A/B/… with extremely thin A and B layers, maximize the effects of interfaces over bulk effects. Particularly relevant are complex oxides superlattices, permitting enhancement or even creation of ferromagnetism and ferroelectricity. The fabrication of oxide superlattices is challenging and requests advanced tools and methodologies of thin film growth. The state-of-the-art pulsed laser deposition (PLD) with real-time control by reflection high energy electron diffraction (RHEED) facilities at ICMAB (http:// www.icmab.es/icmab/scientific-technical-services/thin-films/equipments.html) are the optimal set-ups. The student will investigate the thin film growth mechanism in complex epitaxial multilayers formed by ferroelectric (FE: BaTiO3) and paraelectric (PE: SrTiO3 and CaTiO3) films. N x (n x FE / m x PE) multilayers (N = 1 to 50), with n and m ranging from 1 to 10 unit cells. The student will conduct detailed analysis of 1) RHEED patterns, and particularly of the specular spot intensity oscillations, and 2) atomic force microscopy (AFM) topographic images and X-ray diffraction (XRD) patterns.

 

Interested candidates should contact:

Florencio Sánchez

Institut de Ciència de Materials de Barcelona ICMAB-CSIC,

Campus de la UAB, 08193 Bellaterra, Spain

fsanchez@icmab.es Phone: +34 93 580 18 53 (327)

 

 

Atomic control of single crystalline oxide surfaces for tailored epitaxial growth

Accurate manipulation of the surface of single crystalline oxide substrates is being used recently to tune the epitaxial growth of subsequently deposited films (see for instance R. Bachelet, C. Ocal, L. Garzón, J. Fontcuberta, and F. Sánchez, Conducted growth of SrRuO3 nanodot arrays on self-ordered La0.18Sr0.82Al0.59Ta0.41O3(001) surfaces, Applied Physics Letters 99, 051914 (2011), and references therein). The single crystals are typically perovskite oxides, and the main characteristics considering the use as substrate are morphology and chemical termination. Morphology is characterized by terraces (around 100 nm wide) having a single or two chemical terminations separated by steps (around 0.2 or 0.4 nm high) that can be highly disordered or form well ordered patterns. The objective is to control the chemical termination and the steps-terraces morphology of single crystalls usually used as substrates: SrTiO3(001) and LSAT(001). The student will perform chemical and thermal treatments of the substrates and detailed characterization of the surface by atomic force microscopy (AFM). The engineered substrates will then used to grow epitaxial films of ferromagnetic and ferroelectric oxides, and the impact on the growth mode and film properties will be determined.

 

Interested candidates should contact:

Florencio Sánchez

Institut de Ciència de Materials de Barcelona ICMAB-CSIC,

Campus de la UAB, 08193 Bellaterra, Spain

fsanchez@icmab.es Phone: +34 93 580 18 53 (327)

 

 

Mapping electric transport and capacitance at nanoscale

Nanodevices as used in present and future electronic technologies require mapping of materials’ electric and dielectric properties at nanoscale. We aim to contribute to this development by measuring the dielectric response of nanometric thin films of selected insulating materials. The final goal is to determine to what extent substrate-induced strain may induce radically new properties, such as ferroelectricity, in the films. The student will participate in thin film characterization by atomic force microscopy (AFM), current sensing AFM and capacitance microscopy.

 

Interested candidates should contact:

Josep Fontcuberta & Diego Gutierrez

Institut de Ciència de Materials de Barcelona ICMAB-CSIC
Campus de la UAB,
08193 Bellaterra, Spain
fontcuberta@icmab.es

Phone: +34 93 580 18 53 (228)

 

Magnetoelectric coupling in multiferroic thin films and superlattices

The aim of this project is the magnetodielectric characterization of multiferroic materials in thin film form. Multiferroics are functional oxides in which at least two ferroic orders coexist (for instance, ferroelectricity and ferromagnetism), and are interesting for a variety of applications, such as magnetic memories or tunable high-frequency devices.

The research involves ferroelectric and dielectric measurements at cryogenic temperatures and under magnetic fields, of thin films and multilayers candidate to display multiferroicity.

The work will include also the correlation of the obtained magnetoelectric properties with microstructure, nanostructure and synthesis conditions, so that the student will adquire experience on the characterization of dielectric and ferroelectric materials, on the physics of multiferroic oxides and on other materials science aspects as structural characterization and thin film fabrication.

 

Interested candidates should contact:

Lourdes Fàbrega

Institut de Ciència de Materials de Barcelona ICMAB-CSIC
Campus de la UAB,
08193 Bellaterra, Spain

lourdes@icmab.es

Phone: +34 93 580 18 53 (ext. 313)