Anna Fontcuberta i Morral

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A vertical pillar shadow epitaxy technique is introduced for fabricating coplanar striped or cross-hatched GaAsAlAs two-dimensional heterostructures, where the pattern area of each individual layer can be varied in situ. An array of vertical pillars is mou ...

Diamond is one of the most promising materials for high power and extreme conditions electronics. For this to become a reality, incorporation of active dopants needs to be understood. In this article we demonstrate how cathodoluminescence spectroscopy can ...

Self-catalyzed growth of axial InxGa1-xAs/GaAs heterostructures has been realized by molecular beam epitaxy. The growth of the wires is achieved from gallium/indium alloy droplets that are nucleated in situ. By variation of the In/Ga beam flux during the g ...

Nanowire diameter has a dramatic effect on the absorption cross-section in the optical domain. The maximum absorption is reached for ideal nanowire morphology within a solar cell device. As a consequence, understanding how to tailor the nanowire diameter a ...

Self-assembled nanowire (NW) crystals can be grown into nearly defect-free nanomechanical resonators with exceptional properties, including small motional mass, high resonant frequency and low dissipation. Furthermore, by virtue of slight asymmetries in ge ...

Resonant Raman spectroscopy is realized on closely spaced nanowire-based quantum wells. Phonon quantization consistent with 2.4-nm-thick quantum wells is observed, in agreement with cross-section transmission electron microscopy measurements and photolumin ...

This dataset corresponds to the following manuscript: Zendrini, M., Dubrovskii, V., Rudra, A., Dede, D., Fontcuberta i Morral, A., Piazza, V. “Nucleation-Limited Kinetics of GaAs Nanostructures Grown by Selective Area Epitaxy: Implications for Shape Engi ...

Modulation doped AlGaAs/GaAs core-shell nanowire structures were grown by molecular beam epitaxy. A Si delta-doping was introduced in the AlGaAs shell around the {110} facets of the GaAs core. The wires are typically highly resistive at low temperatures. H ...

In this work, a capacitive sensor based on Anodic Aluminium Oxide (AAO) porous structures has been developed. In some cases, the pores have been also conformally coated with a high chemical pure SiO2 by means of Atomic Layer Deposition (ALD). Temperature m ...

Nanowire-based terahertz photoconductive receivers offer many advantages over the existing bulk-based receivers, such as the capability of measuring the full terahertz polarization state and integrating into micro/nano-systems. However, their detection per ...

The occurrence of heterostructures of cubic silicon/hexagonal silicon as disks defined along the nanowire < 111 > growth direction is reviewed in detail for Si nanowires obtained using Cu as catalyst. Detailed measurements on the structural properties of b ...

GeSn has emerged as a promising semiconductor with optoelectronic functionality in the mid-infrared, with the potential of replacing expensive III-V technology for monolithic on-chip Si photonics. Multiple challenges to achieve optoelectronic-grade GeSn ha ...

We studied a doping series of (110)-oriented AlAs quantum wells (QWs) and observed transport evidence of single anisotropic-mass valley occupancy for the electrons in a 150 Å wide QW. Our calculations of strain and quantum confinement for these samples pre ...

The employment of other group IV materials, such as alloys of germanium and tin, poses a solution for overcoming the efficiency limit of silicon that arises from its indirect bandgap. By using THz spectroscopy, the optoelectronic properties, such as conduc ...

Thermodynamic phase diagrams are the cornerstones to develop synthesis of new materials. Zinc phosphide has evolved into a prospective semicontuctor for next generation solar cells, thanks to its abundance and functional properties. Here we derive an optim ...

Silicon nanowires have been grown with gallium as catalyst by plasma enhanced chemical vapor deposition. The morphology and crystalline structure has been studied by electron microscopy and Raman spectroscopy as a function of growth temperature and catalys ...

Inherent to the nanowire morphology is the exciting possibility of fabricating materials organized at the nanoscale in three dimensions. Composition and structure can be varied along and across the nanowire, as well as within coaxial shells. This opens up ...

The development of low-temperature carbonization procedures promises to provide novel nanostructured carbon materials that are of high current interest in materials science and technology. Here, we report a "wet-chemical" carbonization method that utilizes ...

The synthesis parameter space of bismuth catalyzed germanium nanowires by chemical vapor deposition is determined. The process window for high aspect ratio nanowires is found to be extremely narrow. The optimal conditions are found to be 300 degrees C and ...

The electronic states in a corner-overgrown bent GaAs/AlGaAs quantum well heterostructure are studied with numerical Hartree simulations. Transmission electron microscope pictures of the junction sharpness are shown to justify the sharp-corner potential as ...

Anna Fontcuberta i Morral

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Shadow modulated two-dimensional heterostructures using vertical pillars

Boron quantification, concentration mapping and picosecond excitons dynamics in High-Pressure-High-Temperature diamond by cathodoluminescence

Catalyst-free nanowires with axial InxGa1-xAs/GaAs heterostructures

Tailoring the diameter and density of self-catalyzed GaAs nanowires on silicon

Vectorial scanning force microscopy using a nanowire sensor

Phonon confinement and plasmon-phonon interaction in nanowire-based quantum wells

Nucleation-Limited Kinetics of GaAs Nanostructures Grown by Selective Area Epitaxy: Implications for Shape Engineering in Optoelectronics Devices

Free standing modulation doped core-shell GaAs/AlGaAs hetero-nanowires

A micron‐sized nanoporous multifunction sensing device

Scalable Receivers Based on Horizontally-grown InAs Nanowires Promise All-fiber Terahertz Spectrometer Systems

Influence of the (111) twinning on the formation of diamond cubic/diamond hexagonal heterostructures in Cu-catalyzed Si nanowires

Defects in Ge and GeSn and their impact on optoelectronic properties

Single-valley high-mobility (110) AlAs quantum wells with anisotropic mass

THz characterization of GeSn monocrystalline thin films

Thermodynamic re-assessment of the Zn–P binary system

Gallium assisted plasma enhanced chemical vapor deposition of silicon nanowires

Bandgap engineering in a nanowire: self-assembled 0, 1 and 2D quantum structures

Low-Temperature Preparation of Tailored Carbon Nanostructures in Water

Synthesis parameter space of bismuth catalyzed germanium nanowires

Hartree simulations of coupled quantum Hall edge states in corner-overgrown heterostructures