摘要Within an extended Su–Schrieffer–Heeger model including impurity interactions, the dynamical process of exciton dissociation in the presence of an external electric field is investigated by using a non-adiabatic evolution method. Under the action of impurities, the stability as well as the effective mass of the exciton is reduced. Our results show that the field required to dissociate the excitons depends sensitively on the strength of the impurity potential. As the impurity potential strength increases, the dissociation field decreases effectively. The theoretical results are expected to provide useful predictions concerning which polymers with properly impurity-assisted interactions are likely to be more suitable for use in organic solar cells.
Abstract:Within an extended Su–Schrieffer–Heeger model including impurity interactions, the dynamical process of exciton dissociation in the presence of an external electric field is investigated by using a non-adiabatic evolution method. Under the action of impurities, the stability as well as the effective mass of the exciton is reduced. Our results show that the field required to dissociate the excitons depends sensitively on the strength of the impurity potential. As the impurity potential strength increases, the dissociation field decreases effectively. The theoretical results are expected to provide useful predictions concerning which polymers with properly impurity-assisted interactions are likely to be more suitable for use in organic solar cells.
ZHAO Hong-Xia;ZHAO Hui**;CHEN Yu-Guang
. Dynamical Process of Dissociation of Excitons in Polymer Chains with Impurities[J]. 中国物理快报, 2011, 28(9): 97201-097201.
ZHAO Hong-Xia, ZHAO Hui**, CHEN Yu-Guang
. Dynamical Process of Dissociation of Excitons in Polymer Chains with Impurities. Chin. Phys. Lett., 2011, 28(9): 97201-097201.
[1] Burroughes J H et al 1990 Nature 347 539
[2] Sariciftci N S et al 1992 Science 258 1474
[3] Shaheen S E et al 2001 Appl. Phys. Lett. 78 841
[4] Chandross M et al 1994 Phys. Rev. B 50 14702
[5] Yu G et al 1994 Appl. Phys. Lett. 64 3422
[6] Chen L C et al 2000 Adv. Mater. 12 1367
[7] Halls J J M et al 1995 Nature 376 498
[8] Yu G and Heeger A J 1995 J. Appl. Phys. 78 4510
[9] Gregga B A and Hanna M C 2003 J. Appl. Phys. 93 3605
[10] Popovic Z D et al 1998 Chem. Phys. 127 451
[11] Sariciftci N S and Heeger A J 1997 Handbook of Organic Conductive Molecules and Polymers (New York: Wiley) vol 1 and references therein
[12] Basko D M and Conwell E M 2003 Synth. Meter. 139 819
[13] Arkhipov V I et al 1999 Phys. Rev. Lett. 82 1321
[14] Fu R L, Guo G Y and Sun X 2000 Phys. Rev. B 62 15735
[15] Too C O et al 2001 Synth. Meter. 123 53
[16] Johansson A A and Stafströ m S 2001 Phys. Rev. Lett. 86 3602
[17] Rakhmanova S V and Conwell E M 1999 Appl. Phys. Lett. 75 1518
[18] An Z, Wu C Q and Sun X 2004 Phys. Rev. Lett. 93 216407
[19] Yu J F, Wu C Q, Sun X and Nasu K 2004 Phys. Rev. B 70 064303
[20] Wu C Q, Qiu y, An Z and Nasu K 2003 Phys. Rev. B 68 125416
[21] Yan Y H, An Z and Wu C Q 2004 Euro. Phys. J. B 42 157
[22] Ono Y and Terai A 1990 J. Phys. Soc. Jpn. 59 2893
[23] Liu X, Gao K, Fu J, Li Y, Wei J and Xie S J 2006 Phys. Rev. B 74 172301
[24] Li Y, Gao L, Sun Z, Yin S, Liu D S and Xie S J 2008 Phys. Rev. B 78 014304
[25] Su W P et al 1979 Phys. Rev. Lett. 42 1698
[26] Su W P et al 1980 Phys. Rev. B 22 2099
[27] Brazovskii S A and Kirova N N 1981 Sov. Phys. JETP Lett. 33 4
[28] Ozawa T and Ono Y J 2002 J. Phys. Soc. Jpn. 71 1518
[29] Heeger A J et al 1988 Rev. Mod. Phys. 60 781
[30] Zhao H et al 2008 Phys. Rev. B 78 035209