Coupled-Optical-Phonon-Mode Theory of the Infrared Dispersion in BaTiO3, SrTiO3, and KTaO3

1964 ◽  
Vol 135 (6A) ◽  
pp. A1732-A1737 ◽  
Author(s):  
A. S. Barker ◽  
J. J. Hopfield
Keyword(s):  
Optical Phonon ◽  
Phonon Mode ◽  
Optical Phonon Mode ◽  
Mode Theory

scholarly journals Extremely low-frequency phonon material and its temperature- and photo-induced switching effects

2020 ◽  
Vol 11 (33) ◽  
pp. 8989-8998
Author(s):  
Takaya Yoshida ◽  
Koji Nakabayashi ◽  
Hiroko Tokoro ◽  
Marie Yoshikiyo ◽  
Asuka Namai ◽  
...  
Keyword(s):  
Optical Phonon ◽  
Phonon Mode ◽  
Low Frequency ◽  
Switching Effect ◽  
Two Dimensional ◽  
Optical Phonon Mode ◽  
Extremely Low Frequency

Extremely low-frequency optical phonon mode in Rb-intercalated two-dimensional cyanide-bridged Co–W bimetal assembly and its temperature- and photo-induced switching effect.

Raman-active Fröhlich optical phonon mode in arsenic implanted ZnO

2009 ◽  
Vol 94 (1) ◽  
pp. 011913 ◽  
Author(s):  
J. D. Ye ◽  
S. Tripathy ◽  
Fang-Fang Ren ◽  
X. W. Sun ◽  
G. Q. Lo ◽  
...  
Keyword(s):  
Optical Phonon ◽  
Phonon Mode ◽  
Optical Phonon Mode

scholarly journals Anomalous quantum confinement of the longitudinal optical phonon mode in PbSe quantum dots

2013 ◽  
Vol 88 (11) ◽  
Author(s):  
J. Habinshuti ◽  
O. Kilian ◽  
O. Cristini-Robbe ◽  
A. Sashchiuk ◽  
A. Addad ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Phonon ◽  
Quantum Confinement ◽  
Phonon Mode ◽  
Longitudinal Optical ◽  
Longitudinal Optical Phonon ◽  
Optical Phonon Mode

Coherent optical phonon mode oscillations in wurtzite ZnO excited by femtosecond pulses

2003 ◽  
Vol 93 (8) ◽  
pp. 4939-4941 ◽  
Author(s):  
I. H. Lee ◽  
K. J. Yee ◽  
K. G. Lee ◽  
E. Oh ◽  
D. S. Kim ◽  
...  
Keyword(s):  
Optical Phonon ◽  
Phonon Mode ◽  
Femtosecond Pulses ◽  
Optical Phonon Mode

CHARACTERIZATION OFCdSexS1-xQUANTUM DOTS USING XRD, UV-VIS ABSORPTION AND RAMAN SPECTROSCOPY MEASUREMENTS

2012 ◽  
Vol 11 (02) ◽  
pp. 1250015 ◽  
Author(s):  
JITENDER KUMAR ◽  
SHIKHA MADAN ◽  
DEVINDER MADHWAL ◽  
INDERPREET SINGH ◽  
P. K. BHATNAGAR ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Raman Spectrum ◽  
Optical Phonon ◽  
Phonon Mode ◽  
Hexagonal Phase ◽  
Compressive Strain ◽  
Longitudinal Optical ◽  
Annealing Duration ◽  
Longitudinal Optical Phonon ◽  
Optical Phonon Mode

CdSexS1-xquantum dots (QDs) have been grown in borosilicate glass matrix using two step annealing technique and are characterized by AFM, XRD, UV-Vis absorption, HRTEM and Raman spectroscopy measurements. AFM studies show that nearly spherical clusters of about 5–10 nanocrystals were grown. From XRD measurements, it is found that the nanocrystals are grown in hexagonal phase. From HRTEM measurements, it is observed that the size of QDs increases from 5.1 to 9.5 nm with increasing annealing duration from 3 to 10 hrs. Blue shift in absorption spectrum indicates that quantum confinement increases with decreasing annealing durations. Raman spectrum of CdSexS1-xQDs shows two mode type of behavior i.e., CdSe like longitudinal optical phonon mode (LO1) and CdS like longitudinal optical phonon mode (LO2). It has been observed that with increasing the size of QDs from 5.1 to 9.5 nm, LO1shifts from 205 to 210 cm-1while LO2shifts from 278 to 291 cm-1. The shift in the LO1and LO2Raman peaks towards high frequencies has been interpreted due to increase in the lattice compressive strain with the increase in QDs size. The effect of phonon negative dispersion on the shift of LO1and LO2is found to be comparatively insignificant. It is also found that the ratio of intensity of overtones to the fundamental mode increases from 0.34 to 0.48 with decreasing QD size. This indicates that the electron–phonon coupling increases with the decrease in size of QD due to increasing overlap of electron and hole wave function in small size QDs. It is further observed that the frequency of the surface optical phonon mode remains unchanged as the size of QD changes but the intensity decreases with the increase in the size of QDs finally merging in LO mode Raman spectrum.

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