New many-body mechanism of intraband carrier relaxation in quantum dots embedded in doped heterostructures

• Published in: Solid state communications Vol. 128; no. 6; pp. 219 - 223
• Main Authors: Fedorov, A.V., Baranov, A.V., Rukhlenko, I.D., Masumoto, Y.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01-11-2003; Elsevier
• Subjects: A. Quantum dot; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Collective excitations (including plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Intraband carrier relaxation; D. Surface plasmon–LO–phonon modes; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Quantum dots; Surface and interface electron states; D. Intraband carrier relaxation; 78.67.Hc; D. Surface plasmon–LO–phonon modes; 73.22.Lp; A. Quantum dot; Fluctuations; Gallium arsenides; Inorganic compounds; Charge carriers; Quantum dots; Doping; Theoretical study; Binary compounds; Electron charge distribution; Surface plasmons; Relaxation; Phonon mode; Vibrational modes; D. Surface plasmon-LO-phonon modes; 78.67.Hc A. Quantum dot; Heterostructures; Collective excitations; III-V semiconductors
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2003.08.019

The role of longitudinal surface collective excitations of doped elements of heterostructure in electronic dynamics of quantum dots was studied theoretically. A new mechanism of intraband quantum dot carrier relaxation is proposed where an interaction between the quantum dot carriers and electric potential induced by charge density fluctuations in the element with frequencies of the surface plasmon–LO–phonon modes is responsible for the process. It has been found that two branches of the surface plasmon–LO–phonon modes of the doped element are effectively involved in the relaxation even in the case when a distance between the element and the quantum dots is relatively long
(50÷150
nm).
The calculations show that relaxation rates about
10
12
s
−1
are expected at the distance of 100 nm rising by an order of magnitude at a distance of 30 nm.