摘要The presence of a strong, changing, randomly-oriented, local electric field, which is induced by the photo-ionization that occurs universally in colloidal semiconductor quantum dots (QDs), makes it difficult to observe the quantum-confined Stark effect in ensemble of colloidal QDs. We propose a way to inhibit such a random electric field, and a clear quantum-confined Stark shift is observed directly in close-packed colloidal QDs. Besides the applications in optical switches and modulators, our experimental results indicate how the oscillator strengths of the optical transitions are changed under external electric fields.
Abstract:The presence of a strong, changing, randomly-oriented, local electric field, which is induced by the photo-ionization that occurs universally in colloidal semiconductor quantum dots (QDs), makes it difficult to observe the quantum-confined Stark effect in ensemble of colloidal QDs. We propose a way to inhibit such a random electric field, and a clear quantum-confined Stark shift is observed directly in close-packed colloidal QDs. Besides the applications in optical switches and modulators, our experimental results indicate how the oscillator strengths of the optical transitions are changed under external electric fields.
WANG Zhi-Bing;ZHANG Hui-Chao;ZHANG Jia-Yu**;Huaipeng Su;Y. Andrew Wang. Quantum-Confined Stark Effect in Ensemble of Colloidal Semiconductor Quantum Dots[J]. 中国物理快报, 2010, 27(12): 127803-127803.
WANG Zhi-Bing, ZHANG Hui-Chao, ZHANG Jia-Yu**, Huaipeng Su, Y. Andrew Wang. Quantum-Confined Stark Effect in Ensemble of Colloidal Semiconductor Quantum Dots. Chin. Phys. Lett., 2010, 27(12): 127803-127803.
[1] Miller D A B et al 1984 Phys. Rev. Lett. 53 2173
[2] See, for example, Helman N C, Roth J E, Bour D P, Altug H and Miller D A B 2005 IEEE J. Sel. Top. Quantum Electron. 11 338
[3] Kuo Y H, Lee Y K et al 2005 Nature 437 1334
[4] Leitsmann R and Bechstedt F 2008 Phys. Rev. B 78 205324
Leitsmann R and Bechstedt F 2009 Phys. Rev. B 80 165402
Wen G W, Lin J Y, Jiang H X and Chen Z 1995 Phys. Rev. B 52 5913
[5] Empedocles S A and Bawendi M G 1997 Science 278 2114
[6] Colvin V L, Cunningham K L and Alivisatos A P 1994 J. Chem. Phys. 101 7122
Sacra A, Norris D J, Murray C B and Bawendi M G 1995 J. Chem. Phys. 103 5236
[7] Fry P W, Itskevich I E, Parnell S R, Finley J J, Wilson L R et al 2000 Phys. Rev. B 62 16784
Fry P W, Itskevich I E, Mowbray D J, Skolnick M S, Finley J J, Barker J A et al 2000 Phys. Rev. Lett. 84 733
[8] Ngo C Y, Yoon S F, Loke W K, Cao Q, Lim D R, Wong V, Sim Y K and Chua S J 2008 Nanoscale Res. Lett. 3 486
[9] Nirmal M, Dabbousi B O, Bawendi M G, Macklin J J et al 1996 Nature 383 802
[10] Krauss T D and Brus L E 1999 Phys. Rev. Lett. 83 4840
[11] Klimov V I, Mikhailovsky A A, McBranch D W, Leatherdale C A, Bawendi M G 2000 Science 287 1011
[12] Heyes C D, Kobitski A Y, Breus V V and Nienhaus G U 2007 Phys. Rev. B 75 125431
[13] Kuno M, Fromm D P, Johnson S T, Gallagher A and Nesbitt D J 2003 Phys. Rev. B 67 125304
[14] Sugisaki M, Ren H, Nair S V, Nishi K and Masumoto Y 2002 Phys. Rev. B 66 235309
[15] Sun Q, Wang Y A, Li L S, Wang D, Zhu T, Xu J, Yang C and Li Y 2007 Nature Photonics 1 717
[16] Scholes G D and Rumbles G 2006 Nature Mater. 5 683
[17] Dabbousi B O, Bawendi M G, Onitsuka O and Rubner M F 1995 Appl. Phys. Lett. 66 1316
[18] Zhao J, Zhang J, Jiang C, Bohnenberger J, Basche T and Mews A 2004 J. Appl. Phys. 96 3206
[19] Yan L, Zhang JY, Cui Y and Qiao Y 2007 Appl. Phys. Lett. 91 243114
[20] See, for example, Califano M, Franceschetti A and Zunger A 2005 Nano Lett. 5 2360
[21] Hu J, Li L, Yang W, Manna L, Wang L and Alivisatos A P 2001 Science 292 2060
[22] Polland H J, Schultheis L, Kuhl J, Gobel E O and Tu C W 1985 Phys. Rev. Lett. 55 2610
[23] Mendez E E, Bastard G, Chang L L, Esaki L, Morkoc H and Fischer R 1982 Phys. Rev. B 26 7101