Thermal Sensitive Quantum and Phonon Confinement in Semiconducting Triangular-Shaped MoS2

2021 ◽  
Author(s):  
Bishnu Pada Majee ◽  
Jay Deep Gupta ◽  
Abhishek Sanskrityayn ◽  
Ashish Kumar Mishra
Keyword(s):  
Phonon Confinement

Raman characterization of phonon confinement and strain effects from latent ion tracks in α‐quartz

2021 ◽  
Author(s):  
Maria C. Garcia Toro ◽  
Miguel L. Crespillo ◽  
Jose Olivares ◽  
Joseph T. Graham
Keyword(s):  
Phonon Confinement ◽  
Strain Effects ◽  
Ion Tracks ◽  
Raman Characterization

Raman scattering crystalline assessment of polycrystalline Cu2ZnSnS4 thin films for sustainable photovoltaic technologies: Phonon confinement model

2014 ◽  
Vol 70 ◽  
pp. 272-280 ◽  
Author(s):  
M. Dimitrievska ◽  
A. Fairbrother ◽  
A. Pérez-Rodríguez ◽  
E. Saucedo ◽  
V. Izquierdo-Roca
Keyword(s):  
Thin Films ◽  
Raman Scattering ◽  
Phonon Confinement ◽  
Photovoltaic Technologies ◽  
Confinement Model

scholarly journals Depth-Resolved Microspectroscopy of Porous Silicon Multilayers

1999 ◽  
Vol 588 ◽  
Author(s):  
S. Manotas ◽  
F. Agulló-Rueda ◽  
J. D. Moreno ◽  
R. J. Martín-Palma ◽  
R. Guerrero-Lemus ◽  
...  
Keyword(s):  
Porous Silicon ◽  
Quantum Confinement ◽  
Silicon Nanocrystals ◽  
Phonon Frequency ◽  
Lattice Mismatch ◽  
High Porosity ◽  
Phonon Confinement ◽  
Heating Effects ◽  
Average Size ◽  
Good Agreement

AbstractWe have measured micro-photoluminescence (PL) and micro-Raman spectra on the cross section of porous silicon multilayers to sample different layer depths. We find noticeable differences in the spectra of layers with different porosity, as expected from the quantum confinement of electrons and phonons in silicon nanocrystals with different average sizes. The PL emission band gets stronger, blue shifts, and narrows at the high porosity layers. The average size can be estimated from the shift. The Raman phonon band at 520 cm−1 weakens and broadens asymmetrically towards the low energy side. The line shape can be related quantitatively with the average size by the phonon confinement model. To get a good agreement with the model we add a band at around 480 cm−1, which has been attributed to amorphous silicon. We also have to leave as free parameters the bulk silicon phonon frequency and its line width, which depend on temperature and stress. We reduced laser power to eliminate heating effects. Then we use the change of frequency with depth to monitor the stress. At the interface with the substrate we find a compressive stress in excess of 10 kbar, which agrees with the reported lattice mismatch. Finally, average sizes are larger than those estimated from PL.

Theoretical Investigation of the Shubnikov-de Haas Magnetoresistance Oscillations in a Quantum well under the Influence of Confined Acoustic Phonons

2018 ◽  
Vol 783 ◽  
pp. 1-11
Author(s):  
Le Thai Hung ◽  
Pham Ngoc Thang ◽  
Nguyen Quang Bau
Keyword(s):  
Magnetic Field ◽  
Quantum Well ◽  
Phonon Confinement ◽  
Acoustic Phonons ◽  
Magnetic Impedance ◽  
Magnetoresistance Oscillations ◽  
The Magnetic Field ◽  
Amplitude Decrease ◽  
Theoretical Results ◽  
Phonon Confinement Effect

The Shubnikov – de Haas magnetoresistance oscillations in the Quantum well (QW) under the influence of confined acoustic phonons, The theoretical results show that the conductivity tensor, the complex magnetic impedance of the magnetic field, the frequency, the amplitude of the laser radiation, the QW width, the temperature of the system and especially the quantum index m characterizes the confinement of the phonon. The amplitude of the oscillations of the Shubnikov-de Haas impedance decreases with the increase of the influence of the confined acoustic phonons. The results for bulk phonons in a QW could be achieved, when m goes to zero. We has been compared with other studies when perform the numerical calculations are also achieved for the GaAs/AlGaAs in the QW. Results show that The Shubnikov-de Haas magnetoresistance oscillations amplitude decrease when phonon confinement effect increasing and when width L of the QW increases to a certain value, The Shubnikov – de Haas magnetoresistance oscillations amplitude completely disappears can not be observed.

Modified phonon confinement model for Raman spectroscopy of nanostructured materials

2010 ◽  
Vol 82 (11) ◽  
Author(s):  
K. Roodenko ◽  
I. A. Goldthorpe ◽  
P. C. McIntyre ◽  
Y. J. Chabal
Keyword(s):  
Raman Spectroscopy ◽  
Nanostructured Materials ◽  
Phonon Confinement ◽  
Confinement Model

Novel Methods of Nanoscale Wire Formation

MRS Bulletin ◽  
1999 ◽  
Vol 24 (8) ◽  
pp. 13-19 ◽  
Author(s):  
S.M. Prokes ◽  
Kang L. Wang
Keyword(s):  
High Performance ◽  
Quantum Wires ◽  
Chemical Properties ◽  
Optical Recording ◽  
Oxide Semiconductor ◽  
Hard Disks ◽  
Phonon Confinement ◽  
Nanoscale Structures ◽  
Reduced Dimensions

In recent years, tremendous interest has been generated in the fabrication and characterization of nanoscale structures such as quantum dots and wires. For example, there is interest in the electronic, magnetic, mechanical, and chemical properties of materials with reduced dimensions. In the case of nanoscale semiconductors, quantum effects are expected to play an increasingly prominent role in the physics of nanostructures, and a new class of electronic and optoelectronic devices may be possible. In addition to new and interesting physics, the formation and characterization of nanoscale magnetic structures could result in higher-density storage capacity in hard disks and optical-recording media. Likewise, phonon confinement leads to a drastic reduction of thermal conductivity and can be used to improve the performance of thermoelectric devices.In 1980, H. Sakaki predicted theoretically that quantum wires may have applications in high-performance transport devices, due to their sawtoothlike density of states (E1/2), where E is the electron energy. Since then, most quantum wires have been made by fabricating a gratinglike gate on top of a two-dimensional (2D) electron gas contained in a semiconductor heterojunction or in metal-oxide-semiconductor structures. By applying a negative gate voltage to the system, its structure can be changed from a 2D to a one-dimensional (1D) regime, where electron confinement is achieved by an electrostatic confining potential. It was not until recently that “physical” semiconductor quantum wires with the demonstrated 1D confinement by physical boundaries began to be fabricated.

LATTICE THERMAL CONDUCTIVITY IN A HOLLOW SILICON NANOWIRE

2005 ◽  
Vol 19 (06) ◽  
pp. 1017-1027 ◽  
Author(s):  
WEI-QING HUANG ◽  
KE-QIU CHEN ◽  
Z. SHUAI ◽  
LINGLING WANG ◽  
WANGYU HU
Keyword(s):  
Thermal Conductivity ◽  
Relaxation Time ◽  
Lattice Thermal Conductivity ◽  
Silicon Nanowire ◽  
Boundary Scattering ◽  
Phonon Confinement ◽  
Time Approximation ◽  
Si Nanowire ◽  
Scattering Mechanisms ◽  
Relaxation Time Approximation

We theoretically investigate the lattice thermal conductivity of a hollow Si nanowire under the relaxation time approximation. The results show that the thermal conductivity in such structure is decreased markedly below the bulk value due to phonon confinement and boundary scattering. The thermal conductivities under different scattering mechanisms are given, and it is found that the boundary scattering is dominant resistive process for the decrease of the thermal conductivity.

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