Search

Your search keyword '"Neda, Pourdavoud"' showing total 2 results
Start Over Author "Neda, Pourdavoud" Language english
2 results on '"Neda, Pourdavoud"'

1. A New Concept in the Design of RF Circuits Using PD SOI MOSFET

Author

Neda Pourdavoud and Arash Daghighi

Subjects
FBSOI, BCSOI, TFSOI, THD, IP3, LNA, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract

Recently, there has been a growing interest in using SOI MOSFET as the device dimension shrinks to nano scale regime. The difference between SOI and Bulk MOSFETs is the presence of a transition in the output conductance frequency response due to the nonzero body resistance. Parameters affected by this transition include: 1- THD 2- IP3, two important figures of merits in the investigation of nonlinear effects in the RF circuits. In this study, a new relation is derived indicating that only by adjusting the body resistance, the transition can be minimized. Then, by the use of a device simulator, a 45 nanometer BC SOI is designed. The results of the simulation verify the derived relation. As a result, an important graph is depicted by which it is possible to select both drain voltage and body resistance in which there is no appearance of transition in the output conductance frequency response. Finally, the improvement in THD, HD3 and IP3 in a LNA by the use of 45 nanometer SOI MOSFET is presented.

Published
2012

2. Room-Temperature Stimulated Emission and Lasing in Recrystallized Cesium Lead Bromide Perovskite Thin Films

Author

Yana Vaynzof, Klaus Meerholz, Martin Koch, Tobias Haeger, Neda Pourdavoud, Andre Mayer, Anna Lena Giesecke, Marko Cehovski, Stefan Zaefferer, Hella-Christin Scheer, Thomas Riedl, Ralf Heiderhoff, P. J. Cegielski, Max C. Lemme, Wolfgang Kowalsky, Ivan Shutsko, Ouacef Charfi, Hans-Hermann Johannes, Detlef Rogalla, David Becker-Koch, Patrick Görrn, Andreas Henkel, Markus Stein, and Selina Olthof

Subjects
Amplified spontaneous emission, Photoluminescence, Materials science, business.industry, Mechanical Engineering, Halide, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, Mechanics of Materials, Optoelectronics, General Materials Science, Light emission, Stimulated emission, Thin film, 0210 nano-technology, business, Lasing threshold, Perovskite (structure)
Abstract

Cesium lead halide perovskites are of interest for light-emitting diodes and lasers. So far, thin-films of CsPbX3 have typically afforded very low photoluminescence quantum yields (PL-QY < 20%) and amplified spontaneous emission (ASE) only at cryogenic temperatures, as defect related nonradiative recombination dominated at room temperature (RT). There is a current belief that, for efficient light emission from lead halide perovskites at RT, the charge carriers/excitons need to be confined on the nanometer scale, like in CsPbX3 nanoparticles (NPs). Here, thin films of cesium lead bromide, which show a high PL-QY of 68% and low-threshold ASE at RT, are presented. As-deposited layers are recrystallized by thermal imprint, which results in continuous films (100% coverage of the substrate), composed of large crystals with micrometer lateral extension. Using these layers, the first cesium lead bromide thin-film distributed feedback and vertical cavity surface emitting lasers with ultralow threshold at RT that do not rely on the use of NPs are demonstrated. It is foreseen that these results will have a broader impact beyond perovskite lasers and will advise a revision of the paradigm that efficient light emission from CsPbX3 perovskites can only be achieved with NPs.

Published
2019

Catalog

Books, media, physical & digital resources
See catalog results