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13 results on '"Buffaz, Amandine"'

1. Quantum well infrared photodetectors hardiness to the non ideality of the energy band profile

Author

Lhuillier, Emmanuel, Pere-Laperne, Nicolas, Ribet-Mohamed, Isabelle, Rosencher, Emmanuel, Patriarche, Gilles, Buffaz, Amandine, Berger, Vincent, Nedelcu, Alexandru, and Carras, Mathieu

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Other Condensed Matter
Abstract

We report results on the effect of a non-sharp and disordered potential in Quantum Well Infrared Photodetectors (QWIP). Scanning electronic transmission microscopy is used to measure the alloy profile of the structure which is shown to present a gradient of composition along the growth axis. Those measurements are used as inputs to quantify the effect on the detector performance (peak wavelength, spectral broadening and dark current). The influence of the random positioning of the doping is also studied. Finally we demonstrate that QWIP properties are quite robust with regard to the non ideality of the energy band profile.

Published
2010
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2. Interface roughness transport in THz quantum cascade detectors

Author

Lhuillier, Emmanuel, Ribet-Mohamed, Isabelle, Rosencher, Emmanuel, Patriarche, Gilles, Buffaz, Amandine, Berger, Vincent, and Carras, Mathieu

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

Infrared Detectors based on a Quantum Cascade have been proposed to suppress the dark current which is identified as a limiting factor in Quantum Well Infrared Photodetectors. Those detectors have been mostly designed for the 3-5um and 8-12um range of wavelength. For detector operating in the THz range a complete change of regime of transport is expected since the photon energy is lower than the Longitudinal Optical (LO) phonon energy. Using a two dimensional code of transport we have identified Interface Roughness (IR) as the key interaction in such a structure. We have used scanning transmission electron microscopy (STEM) to evaluate the IR parameters (magnitude of the roughness and mean distance between defects) instead of the classical mobility measurements. Finally, we used these parameters to study their influence on the resistance of the device.

Published
2009
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4. Magnetotransport in quantum cascade detectors: analyzing the current under illumination

Author

Buffaz Amandine, Doyennette Laetitia, Berger Vincent, Carras Mathieu, Marcadet Xavier, Jasnot François-Régis, Péré-Laperne Nicolas, de Vaulchier Louis-Anne, Guldner Yves, Carosella Francesca, and Ferreira Robson

Subjects
Materials of engineering and construction. Mechanics of materials, TA401-492
Abstract

Abstract Photocurrent measurements have been performed on a quantum cascade detector structure under strong magnetic field applied parallel to the growth axis. The photocurrent shows oscillations as a function of B. In order to describe that behavior, we have developed a rate equation model. The interpretation of the experimental data supports the idea that an elastic scattering contribution plays a central role in the behavior of those structures. We present a calculation of electron lifetime versus magnetic field which suggests that impurities scattering in the active region is the limiting factor. These experiments lead to a better understanding of these complex structures and give key parameters to optimize them further.

Published
2011

5. Quantum well infrared photodetectors hardiness to the nonideality of the energy band profile.

Author

Lhuillier, Emmanuel, Péré-Laperne, Nicolas, Ribet-Mohamed, Isabelle, Rosencher, Emmanuel, Patriarche, Gilles, Buffaz, Amandine, Berger, Vincent, Nedelcu, Alexandru, and Carras, Mathieu

Subjects
QUANTUM wells, OPTOELECTRONIC devices, DETECTORS, SEMICONDUCTOR doping, ENERGY bands
Abstract

We report results on the effect of a nonsharp and disordered potential in quantum well infrared photodetectors (QWIP). Scanning electronic transmission microscopy is used to measure the alloy profile of the structure which is shown to present a gradient of composition along the growth axis. Those measurements are used as inputs to quantify the effect on the detector performance (peak wavelength, spectral broadening, and dark current). The influence of the random positioning of the doping is also studied. Finally we demonstrate that QWIP properties are quite robust with regard to the nonideality of the energy band profile. [ABSTRACT FROM AUTHOR]

Published
2010
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6. Space charge mediated negative di erential resistance in terhertz quantum well detectors

Author

Delga, Alexandre, Doyennette, Laetitia, Buffaz, Amandine, Berger, Vincent, Jasnot, François-Régis, Péré-Laperne, Nicolas, de Vaulchier, Louis-Anne, Liu, H.C., Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Pierre Aigrain (LPA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute for Microstructural Sciences (NRC - IMS), National Research Council of Canada (NRC), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Abstract

International audience; In THz Quantum Well Infrared Photodetectors, a built-in-charge-mediated regime transition of the electronic transport is thoroughly investigated. The very strong current discontinuity and neg- ative di erential resistivity behavior are explained in terms of band structure reorganizations. The analysis of bias versus current measurements reveals that the transition occurs when the rst two wells of the structure become partially drained, and that second well enters the ionized regime before the rst one. Both many body e ects and a careful model of the contact have to be considered to account for these features. The probable source of the built-in charge is identi ed as Intersubband Impact Ionization, of which this regime transition would be one of the few experimental evidence, and provide an original approach to investigate hot electrons kinetics in these structures.

Published
2011

7. Negative dierential resistance in terahertz quantum well detectors

Author

Delga, Alexandre, Doyennette, Laetitia, Buffaz, Amandine, Berger, Vincent, Jasnot, François-Régis, Péré-Laperne, Nicolas, de Vaulchier, Louis-Anne, Liu, H.C., Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Pierre Aigrain (LPA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institute for Microstructural Sciences (NRC - IMS), National Research Council of Canada (NRC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Abstract

In THz QWIPs, quantum well impact ionization rules electronic transport between two dierent regimes separated by huge shifts in the current and negative dierential resistivity behavior. This paper is dedicated to give some insight into the microscopic transport physical mechanism. The investigation of bias versus current measurements reveals that the rst two wells of the structure become partially drained, and that second well enters the ionized regime before the rst one. Both many body eects and a careful model of the contact have to be considered to account for these features. The use of this mechanism can lead to the design of very high gain fast THz detectors.

Published
2010

8. Impact Ionization in THz QWIPs: Investigating the 3D Electron Distribution and Designing New Devices

Author

Delga, Alexandre, Buffaz, Amandine, Doyennette, Laetitia, Carras, Mathieu, Jasnot, François-Régis, de Vaulchier, Louis-Anne, Liu, H.C., Berger, Vincent, Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Alcatel Thales 3-5 lab, THALES, Laboratoire Pierre Aigrain (LPA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute for Microstructural Sciences (NRC - IMS), National Research Council of Canada (NRC), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Alcatel-Thalès III-V lab (III-V Lab), THALES [France]-ALCATEL, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Published
2010

9. Metal-Insulator Transition in a Quantum Well Infrared Detector

Author

Buffaz, Amandine, Gomez, Aurore, Doyennette, Laetitia, Jasnot, François-Régis, Péré-Laperne, Nicolas, De Vaulchier, Louis-Anne, Carras, Mathieu, Liu, H.C., Wasilewski, Z.R., Berger, Vincent, Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Thales Research and Technology [Palaiseau], THALES [France], Laboratoire Pierre Aigrain (LPA), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Alcatel-Thalès III-V lab (III-V Lab), THALES [France]-ALCATEL, Institute for Microstructural Sciences (NRC - IMS), National Research Council of Canada (NRC), THALES, Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Alcatel Thales 3-5 lab, and Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Published
2009

10. Photocurrent analysis of quantum cascade detectors by magnetotransport

Author

Jasnot, François-Régis, primary, Péré-Laperne, Nicolas, additional, de Vaulchier, Louis-Anne, additional, Guldner, Yves, additional, Carosella, Francesca, additional, Ferreira, Robson, additional, Buffaz, Amandine, additional, Doyennette, Laetitia, additional, Berger, Vincent, additional, Carras, Mathieu, additional, and Marcadet, Xavier, additional

Published
2010
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