Excitation energy dependent efficiency of charge carrier relaxation and photoluminescence in colloidal InP quantum dots

被引：65

作者：

Ellingson, RJ ^{[1
]}

Blackburn, JL ^{[1
]}

Yu, PR ^{[1
]}

Rumbles, G ^{[1
]}

Micic, OI ^{[1
]}

Nozik, AJ ^{[1
]}

机构：

[1] Natl Renewable Energy Lab, Ctr Basic Sci, Golden, CO 80401 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2002年 / 106卷 / 32期

关键词：

D O I：

10.1021/jp025666p

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Femtosecond transient absorption spectroscopy has been used together with time-integrated photoluminescence (PL) measurements to study charge carrier relaxation in colloidal InP quantum dots (QDs). Measurements of band-edge photoinduced bleaching as well as PL intensity measurements indicate that the fraction of charge carriers relaxing to the band-edge states depends on excitation wavelength, with a markedly reduced relaxation efficiency observed for excitation well above the absorption edge. The results concur with previous research on CdSe and InP QDs, and suggest that with increasing excitation energy there arise relaxation pathways involving surface or external energy states exhibiting reduced radiative efficiency. Such highly excited carriers are either inhibited or deviated from reaching the band-edge states. Excitation intensity dependent measurements indicate that those charge carriers which contribute to the band-edge absorption bleaching also contribute proportionally to the time-integrated PL spectrum.

引用

页码：7758 / 7765

页数：8

共 25 条

[1] Quantum confinement and ultrafast dephasing dynamics in InP nanocrystals [J].

Banin, U ;

Cerullo, G ;

Guzelian, AA ;

Alivisatos, AP ;

Shank, CV .

PHYSICAL REVIEW B, 1997, 55 (11) :7059-7067

[2] INTRINSIC MECHANISM FOR THE POOR LUMINESCENCE PROPERTIES OF QUANTUM-BOX SYSTEMS [J].

BENISTY, H ;

SOTOMAYORTORRES, CM ;

WEISBUCH, C .

PHYSICAL REVIEW B, 1991, 44 (19) :10945-10948

[3] PHONON-SCATTERING AND ENERGY RELAXATION IN 2-DIMENSIONAL, ONE-DIMENSIONAL, AND ZERO-DIMENSIONAL ELECTRON GASES [J].

BOCKELMANN, U ;

BASTARD, G .

PHYSICAL REVIEW B, 1990, 42 (14) :8947-8951

[4] HOT CARRIER INJECTION AT SEMICONDUCTOR-ELECTROLYTE JUNCTIONS [J].

BOUDREAUX, DS ;

WILLIAMS, F ;

NOZIK, AJ .

JOURNAL OF APPLIED PHYSICS, 1980, 51 (04) :2158-2163

[5] Comment on "Comparison of the k•p and the direct diagonalization approaches for describing the electron structure of quantum dots" [J].

Efros, AL ;

Rosen, M .

APPLIED PHYSICS LETTERS, 1998, 73 (08) :1155-1156

[6] Band-edge exciton in quantum dots of semiconductors with a degenerate valence band: Dark and bright exciton states [J].

Efros, AL ;

Rosen, M ;

Kuno, M ;

Nirmal, M ;

Norris, DJ ;

Bawendi, M .

PHYSICAL REVIEW B, 1996, 54 (07) :4843-4856

[7] The electronic structure of semiconductor nanocrystals [J].

Efros, AL ;

Rosen, M .

ANNUAL REVIEW OF MATERIALS SCIENCE, 2000, 30 :475-521

[8] Many-body pseudopotential theory of excitons in InP and CdSe quantum dots [J].

Franceschetti, A ;

Fu, H ;

Wang, LW ;

Zunger, A .

PHYSICAL REVIEW B, 1999, 60 (03) :1819-1829

[9] Comment on "Comparison of the k•p and the direct diagonalization approaches for describing the electron structure of quantum dots" -: Response [J].

Fu, HX ;

Wang, LW ;

Zunger, A .

APPLIED PHYSICS LETTERS, 1998, 73 (08) :1157-1158

[10] Excitons in InP quantum dots [J].

Fu, HX ;

Zunger, A .

PHYSICAL REVIEW B, 1998, 57 (24) :15064-15067

← 1 2 3 →