Relation between size dispersion and line shape in quantum dot ensembles

2009 ◽  
Vol 95 (26) ◽  
pp. 263107 ◽  
Author(s):  
V. V. Nikolaev ◽  
N. S. Averkiev
Keyword(s):  
Quantum Dot ◽  
Line Shape ◽  
Size Dispersion

Theory of the Raman-scattering intensity and line shape of a quantum-dot superlattice

1991 ◽  
Vol 44 (19) ◽  
pp. 10744-10748 ◽  
Author(s):  
Chao Zhang ◽  
Godfrey Gumbs ◽  
Danhong Huang
Keyword(s):  
Quantum Dot ◽  
Raman Scattering ◽  
Line Shape ◽  
Scattering Intensity

scholarly journals Universal line shape of the Kondo zero-bias anomaly in a quantum dot

2012 ◽  
Vol 85 (20) ◽  
Author(s):  
Andrey V. Kretinin ◽  
Hadas Shtrikman ◽  
Diana Mahalu
Keyword(s):  
Quantum Dot ◽  
Line Shape ◽  
Zero Bias ◽  
Zero Bias Anomaly

BROADENING OF FANO RESONANCE IN ELECTRONIC CURRENT THROUGH A QUANTUM DOT BY DEPHASING

2002 ◽  
Vol 16 (10) ◽  
pp. 1479-1487 ◽  
Author(s):  
YONG-JIAN XIONG ◽  
SHI-JIE XIONG
Keyword(s):  
Electron Transport ◽  
Quantum Dot ◽  
Line Shape ◽  
Fano Resonance ◽  
Resonance Peak ◽  
Half Width ◽  
Electronic Current

We investigate the Fano line shape in electron transport through a quantum dot in presence of dephasing. The dephasing effect is introduced by the Büttiker model. We derive a generalized Fano formula for the conductance that includes the components of the standard Fano line shape and the Breit–Wigner line shape. According to this formula the Fano parameter |q| decreases when the dephasing strength increases by increasing the temperature. The increase of the half width of the resonance peak by increasing the temperature measured by Zacharia et al. [Phys. Rev.B64, 155311 (2001)] which is more rapid than expected from the ordinary theories is possibly attributed to the dephasing.

Thermally-activated effects on photoluminescence line shape of InAs/GaAs quantum dot heterosystems

2007 ◽  
Vol 38 (1) ◽  
pp. 21-25 ◽  
Author(s):  
Jiunn-Chyi Lee ◽  
Yeu-Jent Hu ◽  
Ya-Fen Wu ◽  
Jia-Hui Fang ◽  
Tzer-En Nee ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Line Shape ◽  
Thermally Activated ◽  
Photoluminescence Line ◽  
Gaas Quantum Dot

THEORY OF THRESHOLD CHARACTERISTICS OF QUANTUM DOT LASERS: EFFECT OF QUANTUM DOT PARAMETER DISPERSION

2002 ◽  
Vol 12 (01) ◽  
pp. 111-176 ◽  
Author(s):  
LEVON V. ASRYAN ◽  
ROBERT A. SURIS
Keyword(s):  
Quantum Dot ◽  
Temperature Dependence ◽  
Characteristic Temperature ◽  
Threshold Current ◽  
Threshold Current Density ◽  
Hole Burning ◽  
Charge Neutrality ◽  
Generation Threshold ◽  
Carrier Recombination ◽  
Size Dispersion

Gain and threshold current of a quantum dot (QD) laser are analyzed theoretically taking into account the inhomogeneous line broadening caused by fluctuations in QD parameters. Two regions of QD filling by carriers, nonequilibrium and equilibrium, are identified, depending on temperature, barrier heights and QD size. Critical tolearable parameters of the QD structure, at which lasing becomes impossible to attain, are shown to exist. The minimum threshold current density and optimum parameters are calculated. Violation of charge neutrality in QDs is revealed, which affects significantly the threshold current and its temperature dependence. The gain-current dependence is calculated. The voltage dependences of the electron and hole level occupancies in QDs, gain and current are obtained. The observed temperature dependence of threshold current (constant at low temperatures and rapid increase above a certain temperature) is predicted and explained. Violation of charge neutrality is shown to give rise to the slight temperature dependence of the current component associated with the recombination in QDs. The characteristic temperature T0 is calculated considering carrier recombination in the optical confinement layer and violation of charge neutrality in QDs. The inclusion of violation of charge neutrality is shown to be critical for the correct calculation of T0 at low T. T0 is shown to fall off profoundly with increasing T. Theoretical estimations confirm the possibility of a significant reduction of the threshold currents and enhancement of T0 of QD lasers as compared with the conventional quantum wall (QW) lasers. Longitudinal spatial hole burning is analyzed. Unlike QW lasers, thermally excited escapes of carrier from QDs, rather than diffusion, are shown to control the smoothing-out of the spatially nonuniform population inversion and multimode generation in QD lasers. A decrease in the QD size dispersion is shown not only to decrease the threshold current but to increase considerably the relative multimode generation threshold as well. Concurrent with the increase of threshold current, an increase of the multimode generation threshold is shown to occur with a rise in temperature. Ways to optimize the QD laser, aimed at maximizing the multimode generation threshold, are outlined.

Sign in / Sign up

Export Citation Format

Share Document