Quantized acoustic phonon modes in quantum wires and quantum dots

1994 ◽  
Vol 76 (8) ◽  
pp. 4670-4675 ◽  
Author(s):  
Michael A. Stroscio ◽  
K. W. Kim ◽  
SeGi Yu ◽  
Arthur Ballato
Keyword(s):  
Quantum Dots ◽  
Acoustic Phonon ◽  
Quantum Wires ◽  
Phonon Modes

scholarly journals Acoustic phonon modes of rectangular quantum wires

1997 ◽  
Vol 9 (27) ◽  
pp. 5751-5764 ◽  
Author(s):  
N Nishiguchi ◽  
Y Ando ◽  
M N Wybourne
Keyword(s):  
Acoustic Phonon ◽  
Quantum Wires ◽  
Phonon Modes ◽  
Rectangular Quantum Wires

Zinc Blende 0D Quantum Dots to Wurtzite 1D Quantum Wires: The Oriented Attachment and Phase Change in ZnSe Nanostructures

2013 ◽  
Vol 4 (19) ◽  
pp. 3292-3297 ◽  
Author(s):  
Suresh Sarkar ◽  
Shinjita Acharya ◽  
Arup Chakraborty ◽  
Narayan Pradhan
Keyword(s):  
Quantum Dots ◽  
Phase Change ◽  
Quantum Wires ◽  
Oriented Attachment ◽  
Zinc Blende

Quantized Acoustic-Phonon Modes in Metallic Nanowire Structures

2015 ◽  
Vol 44 (12) ◽  
pp. 3019-3022 ◽  
Author(s):  
Hou Yuexia ◽  
Xu Wen ◽  
Hu Jiaguang ◽  
Xiao Yiming
Keyword(s):  
Acoustic Phonon ◽  
Phonon Modes

Guided Acoustic Phonon Modes in Layered Anisotropic Nanowires

2003 ◽  
Author(s):  
Osama M. Mukdadi ◽  
Subhendu K. Datta ◽  
Martin L. Dunn
Keyword(s):  
Thermal Conductivity ◽  
Acoustic Phonon ◽  
Energy Transport ◽  
Bulk Material ◽  
Rectangular Cross Section ◽  
Critical Role ◽  
Acoustic Phonons ◽  
Phonon Modes ◽  
Low Velocity ◽  
Analysis Technique

Acoustic phonons play a critical role in energy transport in nanostructures. The dispersion of acoustic phonons strongly influences thermal conductivity. Recent observations show lower values of thermal conductivity in finite dimensional nanostructures than in the bulk material. In this work, we will present results for guided acoustic phonon modes in (a) a bilayered GaAs-Nb nanowire of rectangular cross section and (b) a trapezoidal Si nanowire. The former has been used for phonon counting in a nanocalorimeter for measuring thermal conductivity and the latter is commonly used in MEMS applications. A semi-analytical finite element (SAFE) analysis technique has been used to investigate the effects of layering, anisotropy, and boundaries on the dispersion of modes of propagation. Many interesting features of group velocities are found that show confinements around the corners, in the low velocity layer, and coupling of the longitudinal and flexural modes. These would strongly influence thermal conductivity and might provide means of nondestrutive evaluation of mechanical properties.

Ultrafast Carrier Dynamics, Optical Amplification, and Lasing in Nanocrystal Quantum Dots

MRS Bulletin ◽  
2001 ◽  
Vol 26 (12) ◽  
pp. 998-1004 ◽  
Author(s):  
Victor I. Klimov ◽  
Moungi G. Bawendi
Keyword(s):  
Quantum Dots ◽  
Quantum Wells ◽  
Quantum Wires ◽  
Electronic States ◽  
Three Dimensions ◽  
Band Edge ◽  
Lasing Threshold ◽  
Wide Energy Range ◽  
Band Edge Emission ◽  
Edge States

Semiconductor materials are widely used in both optically and electrically pumped lasers. The use of semiconductor quantum wells (QWs) as optical-gain media has resulted in important advances in laser technology. QWs have a two-dimensional, step-like density of electronic states that is nonzero at the band edge, enabling a higher concentration of carriers to contribute to the band-edge emission and leading to a reduced lasing threshold, improved temperature stability, and a narrower emission line. A further enhancement in the density of the band-edge states and an associated reduction in the lasing threshold are in principle possible using quantum wires and quantum dots (QDs), in which the confinement is in two and three dimensions, respectively. In very small dots, the spacing of the electronic states is much greater than the available thermal energy (strong confinement), inhibiting thermal depopulation of the lowest electronic states. This effect should result in a lasing threshold that is temperatureinsensitive at an excitation level of only 1 electron-hole (e-h) pair per dot on average. Additionally, QDs in the strongconfinement regime have an emission wavelength that is a pronounced function of size, adding the advantage of continuous spectral tunability over a wide energy range simply by changing the size of the dots.

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