Search results for "Optoelectronic device"
showing 4 items of 14 documents
Bi3+doping in 1D ((CH3)3SO)PbI3: A model for defect interactions in halide perovskites
2022
The recently described monodimensional hybrid pseudo-perovskite ((CH3)3SO)PbI3 exhibits complete Pb2+/Bi3+ miscibility in the B site. Heterovalent substitution imposes that charge-compensating defects are introduced in the lattice as well. This paper reports the energetics of point defects and the interaction between charge-compensating defects that occur upon Bi3+ doping in ((CH3)3SO)PbI3. Periodic DFT simulations were employed to analyze the formation energy of Pb2+ vacancies, (CH3)3SO+ vacancies, iodide vacancies, or the insertion of interstitial iodide ions. Solid solutions with a large Bi3+ content were modeled considering different charge compensation defects (Pb2+ vacancies, (CH3)3SO…
Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange
2004
The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.
Preparation and characterisation of optical and optoelectronic devices based in two-dimensional semiconductors
2020
In the Materials Science field, two-dimensional materials have gained the scientific community attention in recent years. The change and the appearance of novel properties when their thickness is reduced to nanometric scale has special interest for its fundamental properties study for, from this base, the design and its implementation in devices. The wide variety of materials with the possibility of being exfoliated at the two-dimensional level opens the field to different applications, from optoelectronic devices, detection and sensing, energy storage, catalysis, medical applications and quantum information technologies, among others. This thesis gathers results in both directions: a funda…
Validity and Reliability of a New Optoelectronic System for Measuring Active Range of Motion of Upper Limb Joints in Asymptomatic and Symptomatic Sub…
2019
The aim of this study was to evaluate the validity of the Veloflex infrared dynamic angle-meter (Veloflex-IDA) and the intra- and inter-rater reliability when measuring the ranges of motion (ROMs) of the upper limb joints. Thirty-five healthy and 20 symptomatic participants were evaluated. Twelve upper limb movements were measured in two sessions with the Veloflex-IDA, which is a device composed of a camera that tracks the trajectory of retro-reflective markers. In addition, a goniometer was used in the first session to evaluate concurrent validity. Validity and agreement were evaluated by Pearson correlation coefficient (r) and Bland&ndash