Raman spectra of CdS nanocrystals in Nafion: longitudinal optical and confined acoustic phonon modes

被引：86
作者：
Nandakumar, P
Vijayan, C [1 ]
Rajalakshmi, M
Arora, AK
Murti, YVGS
机构：
[1] Indian Inst Technol, Dept Phys, Madras 600036, Tamil Nadu, India
[2] Indira Gandhi Ctr Atom Res, Div Mat Sci, Kalpakkam 603102, Tamil Nadu, India
[3] Indian Inst Technol, Dept Phys, Gauhati 781001, India
来源：
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES | 2001年 / 11卷 / 04期
关键词：
semiconductor quantum dots; Raman spectra; LO-phonon modes; acoustic phonons; strong confinement;
D O I：
10.1016/S1386-9477(01)00157-6
中图分类号：
TB3 [工程材料学];
学科分类号：
0805 ; 080502 ;
摘要：
Quantum confinement effects on the longitudinal optical and acoustic phonons in US nanocrystals in the strongly confined regime in the polymer matrix Nafion are studied using Raman spectroscopy. The LO-phonon modes show size-dependent asymmetric broadening though the broadening and asymmetry are less than those predicted by the phonon confinement models. Two types of confined acoustic modes corresponding to n = 1, l = 0 and n = 1, l = 2 spheroidal vibrations are observed. Softening of the spheroidal modes is observed in the strongly confined regime. (C) 2001 Elsevier Science B.V. All rights reserved.
引用
收藏
页码：377 / 383
页数：7
相关论文
共 24 条
[1]   THE EFFECTS OF MICROCRYSTAL SIZE AND SHAPE ON THE ONE PHONON RAMAN-SPECTRA OF CRYSTALLINE SEMICONDUCTORS [J].
CAMPBELL, IH ;
FAUCHET, PM .
SOLID STATE COMMUNICATIONS, 1986, 58 (10) :739-741
[2]   THEORY OF ONE-PHONON RAMAN-SCATTERING IN SEMICONDUCTOR MICROCRYSTALLITES [J].
CHAMBERLAIN, MP ;
TRALLEROGINER, C ;
CARDONA, M .
PHYSICAL REVIEW B, 1995, 51 (03) :1680-1693
[3]   SIZE OF CD(S,SE) QUANTUM DOTS IN GLASSES - CORRELATION BETWEEN MEASUREMENTS BY HIGH-RESOLUTION TRANSMISSION ELECTRON-MICROSCOPY, SMALL-ANGLE X-RAY-SCATTERING, AND LOW-FREQUENCY INELASTIC RAMAN-SCATTERING [J].
CHAMPAGNON, B ;
ANDRIANASOLO, B ;
RAMOS, A ;
GANDAIS, M ;
ALLAIS, M ;
BENOIT, JP .
JOURNAL OF APPLIED PHYSICS, 1993, 73 (06) :2775-2780
[4]   VIBRATION EIGENMODES AND SIZE OF MICROCRYSTALLITES IN GLASS - OBSERVATION BY VERY-LOW-FREQUENCY RAMAN-SCATTERING [J].
DUVAL, E ;
BOUKENTER, A ;
CHAMPAGNON, B .
PHYSICAL REVIEW LETTERS, 1986, 56 (19) :2052-2055
[5]  
GERULLO G, 1999, PHYS REV B, V60, P1928
[6]   Size-dependent surface phonon mode of CdSe quantum dots [J].
Hwang, YN ;
Park, SH ;
Kim, D .
PHYSICAL REVIEW B, 1999, 59 (11) :7285-7288
[7]   SIZE DEPENDENCE OF ELECTRON-PHONON COUPLING IN SEMICONDUCTOR NANOSPHERES - THE CASE OF CDSE [J].
KLEIN, MC ;
HACHE, F ;
RICARD, D ;
FLYTZANIS, C .
PHYSICAL REVIEW B, 1990, 42 (17) :11123-11132
[8]  
Lamb H., 1882, P MATH SOC LONDON, V13
[9]   Photoacoustic response of CdS quantum dots in nafion [J].
Nandakumar, P ;
Dhobale, AR ;
Babu, Y ;
Sastry, MD ;
Vijayan, C ;
Murti, YVGS ;
Dhanalakshmi, K ;
Sundararajan, G .
SOLID STATE COMMUNICATIONS, 1998, 106 (04) :193-196
[10]   Synthesis and characterization of CdS nanocrystals in a perfluorinated ionomer (Nafion) [J].
Nandakumar, P ;
Vijayan, C ;
Dhanalakshmi, K ;
Sundararajan, G ;
Nair, PK ;
Murti, YVGS .
MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, 2001, 83 (1-3) :61-65
123