Two-step field-induced singlet dissociation in a fluorene trimer

被引：20

作者：

Cabanillas-Gonzalez, J ^{[1
]}

Antognazza, MR

Virgili, T

Lanzani, G

Gadermaier, C

Sonntag, M

Strohriegl, P

机构：

[1] Politecn Milan, IFN CNR, Dipartimento Fis, ULTRAS INFM, I-20133 Milan, Italy

[2] Graz Univ Technol, Inst Festkorperphys, Christian Doppler Lab Adv Funct Mat, A-8010 Graz, Austria

[3] Univ Bayreuth, Lehrstuhl Makromol Chem 1, D-95440 Bayreuth, Germany

来源：

PHYSICAL REVIEW B | 2005年 / 71卷 / 15期

关键词：

D O I：

10.1103/PhysRevB.71.155207

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We time resolve the event of singlet separation into free carriers in an oligofluorene using femtosecond field assisted pump-probe technique. Steady state photoinduced absorption (PA) measurements have also been employed to identify triplet absorption (T-1-T-n) in the spectral region of 1.8 eV. As a result of an applied electric field of 2.2 MV/cm singlets are observed to undergo a dissociation process consisting of first singlet splitting into bound polaron pairs and second further dissociation of polaron pairs into free carriers. Subsequent free carrier recombination yields a new population of singlets and triplets. Our results suggest that nongeminate recombination leads to the formation of 35% singlets and 65% triplets.

引用

页数：7

共 33 条

[1] Photovoltaic performance and morphology of polyfluorene blends: A combined microscopic and photovoltaic investigation [J].

Arias, AC ;

MacKenzie, JD ;

Stevenson, R ;

Halls, JJM ;

Inbasekaran, M ;

Woo, EP ;

Richards, D ;

Friend, RH .

MACROMOLECULES, 2001, 34 (17) :6005-6013

[2] Hot exciton dissociation in a conjugated polymer [J].

Arkhipov, VI ;

Emelianova, EV ;

Bässler, H .

PHYSICAL REVIEW LETTERS, 1999, 82 (06) :1321-1324

[3] A tandem mechanism of charge-carrier photogeneration in disordered organic materials [J].

Arkhipov, VI ;

Emelianova, EV ;

Bässler, H .

CHEMICAL PHYSICS LETTERS, 2001, 340 (5-6) :517-523

[4]

CABANILLASGONZA.J, IN PRESS SYNTH MET

[5] Film morphology and photophysics of polyfluorene [J].

Cadby, AJ ;

Lane, PA ;

Mellor, H ;

Martin, SJ ;

Grell, M ;

Giebeler, C ;

Bradley, DDC ;

Wohlgenannt, M ;

An, C ;

Vardeny, ZV .

PHYSICAL REVIEW B, 2000, 62 (23) :15604-15609

[6] Ultrafast Forster transfer dynamics in tetraphenylporphyrin doped poly(9,9-dioctylfluorene) [J].

Cerullo, G ;

Stagira, S ;

Zavelani-Rossi, M ;

De Silvestri, S ;

Virgili, T ;

Lidzey, DG ;

Bradley, DDC .

CHEMICAL PHYSICS LETTERS, 2001, 335 (1-2) :27-33

[7] POLARON-PAIR GENERATION IN POLY(PHENYLENE VINYLENES) [J].

FRANKEVICH, EL ;

LYMAREV, AA ;

SOKOLIK, I ;

KARASZ, FE ;

BLUMSTENGEL, S ;

BAUGHMAN, RH ;

HORHOLD, HH .

PHYSICAL REVIEW B, 1992, 46 (15) :9320-9324

[8] Ultrafast photoexcitation dynamics in a ladder-type oligophenyl -: art. no. 125203 [J].

Gadermaier, C ;

Cerullo, G ;

Zavelani-Rossi, M ;

Sansone, G ;

Lanzani, G ;

Zojer, E ;

Pogantsch, A ;

Beljonne, D ;

Shuai, Z ;

Brédas, JL ;

Scherf, U ;

Leising, G .

PHYSICAL REVIEW B, 2002, 66 (12) :1252031-1252037

[9] Origin and stabilization of photoexcitations in conjugated polymers [J].

Graupner, W ;

Eder, S ;

Petritsch, K ;

Leising, G ;

Scherf, U .

SYNTHETIC METALS, 1997, 84 (1-3) :507-510

[10] Direct observation of ultrafast field-induced charge generation in ladder-type poly(para-phenylene) [J].

Graupner, W ;

Cerullo, G ;

Lanzani, G ;

Nisoli, M ;

List, EJW ;

Leising, G ;

De Silvestri, S .

PHYSICAL REVIEW LETTERS, 1998, 81 (15) :3259-3262

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