Ultranarrow ionization resonances in a quantum dot under broadband excitation

Gustavsson, S.; Rudner, M.S.; Levitov, L.S.; Leturcq, R.; Studer, M.; Ihn, T.; Ensslin, K.

Type de document :

Compte-rendu et recension critique d'ouvrage

DOI :

10.1103/PhysRevB.89.115304

Titre :

Ultranarrow ionization resonances in a quantum dot under broadband excitation

Auteur(s) :

Gustavsson, S. [Auteur]
Research Laboratory of Electronics [Cambridge] [RLE]
Rudner, M.S. [Auteur]
Department of Physics [Harvard University]
Levitov, L.S. [Auteur]
Department of Physics [MIT Cambridge]
Leturcq, R. [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Studer, M. [Auteur]
Ihn, T. [Auteur]
Ensslin, K. [Auteur]

Titre de la revue :

Physical Review B: Condensed Matter and Materials Physics (1998-2015)

Pagination :

115304, 8 pages

Éditeur :

American Physical Society

Date de publication :

2014-03-15

ISSN :

1098-0121

Discipline(s) HAL :

Sciences de l'ingénieur [physics]

Résumé en anglais : [en]

Semiconductor quantum dots driven by the broadband radiation fields of nearby quantum point contacts provide an interesting setting for probing dynamics in driven quantum systems at the nanoscale. We report on real-time ...
Lire la suite >Semiconductor quantum dots driven by the broadband radiation fields of nearby quantum point contacts provide an interesting setting for probing dynamics in driven quantum systems at the nanoscale. We report on real-time charge-sensing measurements of the dot occupation, which reveal sharp resonances in the ionization rate as a function of gate voltage and applied magnetic field. Despite the broadband nature of excitation, the resonance widths are much smaller than the scale of thermal broadening. We show that such resonant enhancement of ionization is not accounted for by conventional approaches relying on elastic scattering processes, but can be explained via a mechanism based on a bottleneck process that is relieved near excited state level crossings. The experiment thus reveals a regime of a strongly driven quantum dynamics in few-electron systems. The theoretical results are in good agreement with observations.Lire moins >

Langue :

Anglais

Vulgarisation :

Non

Collections :