Noise-induced quantum coherence drives photo-carrier generation dynamics at polymeric semiconductor heterojunctions

Here we report on an exciton/lattice model of the electronic dynamics of primary photo excitations in a polymeric semiconductor heterojunction that includes both polymer π-stacking, energetic disorder and phonon relaxation. Our model indicates that that in polymer/fulerene heterojunction systems, resonant tunnelling processes brought about by environmental fluctuations couple photo excitations directly to photocurrent producing charge-transfer states on <100 fs time scales. Moreover, we find this process to be independent of the location of energetic disorder in the system, and hence we expect exciton fission via resonant tunnelling to polarons to be a ubiquitous feature of these systems.

[1]  Justin R. Caram,et al.  Dynamics of electronic dephasing in the Fenna–Matthews–Olson complex , 2010 .

[2]  Exciton dissociation at donor-acceptor polymer heterojunctions: quantum nonadiabatic dynamics and effective-mode analysis. , 2006, The Journal of chemical physics.

[3]  Marlan O Scully,et al.  Quantum heat engine power can be increased by noise-induced coherence , 2011, Proceedings of the National Academy of Sciences.

[4]  G. Fleming,et al.  Theoretical examination of quantum coherence in a photosynthetic system at physiological temperature , 2009, Proceedings of the National Academy of Sciences.

[5]  D. Haar,et al.  Fluctuation, relaxation and resonance in magnetic systems : Scottish Universities's Summer School, 1961 , 1962 .

[6]  P. Barbara,et al.  Contemporary Issues in Electron Transfer Research , 1996 .

[7]  G. Cerullo,et al.  Quantum coherence controls the charge separation in a prototypical artificial light harvesting system , 2013 .

[8]  Gregory S. Engel,et al.  Quantum coherence spectroscopy reveals complex dynamics in bacterial light-harvesting complex 2 (LH2) , 2012, Proceedings of the National Academy of Sciences.

[9]  Daniel Moses,et al.  Coherence and Uncertainty in Nanostructured Organic Photovoltaics , 2013 .

[10]  David Beljonne,et al.  The Role of Driving Energy and Delocalized States for Charge Separation in Organic Semiconductors , 2012, Science.

[11]  Miao Xu,et al.  Enhanced power-conversion efficiency in polymer solar cells using an inverted device structure , 2012, Nature Photonics.

[12]  R. Silbey,et al.  Exciton–Phonon Interactions in Molecular Crystals , 1970 .

[13]  G. Scholes,et al.  Coherent Intrachain Energy Migration in a Conjugated Polymer at Room Temperature , 2009, Science.

[14]  Niyazi Serdar Sariciftci,et al.  REVERSIBLE, METASTABLE, ULTRAFAST PHOTOINDUCED ELECTRON TRANSFER FROM SEMICONDUCTING POLYMERS TO BUCKMINSTERFULLERENE AND IN THE CORRESPONDING DONOR/ACCEPTOR HETEROJUNCTIONS , 1994 .

[15]  A. Troisi.  How quasi-free holes and electrons are generated in organic photovoltaic interfaces. , 2013, Faraday discussions.

[16]  G. Cerullo,et al.  Hot exciton dissociation in polymer solar cells. , 2013, Nature materials.

[17]  Ultrafast charge separation in organic photovoltaics enhanced by charge delocalization and vibronically hot exciton dissociation. , 2013, Journal of the American Chemical Society.

[18]  N. Banerji.  Sub-picosecond delocalization in the excited state of conjugated homopolymers and donor–acceptor copolymers , 2013 .

[19]  T. Mančal,et al.  Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems , 2007, Nature.

[20]  Nelson E. Coates,et al.  Charge carrier photogeneration and decay dynamics in the poly(2,7-carbazole) copolymer PCDTBT and in bulk heterojunction composites with PC 70 BM , 2010 .

[21]  S. Rice,et al.  Frenkel Excitons in a Vibrating Molecular Crystal , 1970 .

[22]  M. Toney,et al.  A general relationship between disorder, aggregation and charge transport in conjugated polymers. , 2013, Nature materials.

[23]  E. Bittner,et al.  Polaron–excitons and electron–vibrational band shapes in conjugated polymers , 2003 .

[24]  E. Thuneberg,et al.  Motional averaging in a superconducting qubit , 2012, Nature Communications.

[25]  E. Bittner,et al.  Dissipative dynamics of spin-dependent electron–hole capture in conjugated polymers , 2003 .

[26]  Gregory D Scholes,et al.  Long-range resonance energy transfer in molecular systems. , 2003, Annual review of physical chemistry.

[27]  E. Bittner,et al.  Exciton dynamics in disordered poly(p-phenylenevinylene). 2. Exciton diffusion. , 2012, The journal of physical chemistry. A.

[28]  S. Mukamel.  Comment on "Coherence and uncertainty in nanostructured organic photovoltaics". , 2013, The journal of physical chemistry. A.

[29]  E. W. Meijer,et al.  Excitation migration along oligophenylenevinylene-based chiral stacks: delocalization effects on transport dynamics. , 2005, The journal of physical chemistry. B.

[30]  H. Tamura,et al.  Phonon-driven ultrafast exciton dissociation at donor-acceptor polymer heterojunctions. , 2007, Physical review letters.

[31]  Eric Vauthey,et al.  Exciton formation, relaxation, and decay in PCDTBT. , 2010, Journal of the American Chemical Society.

[32]  E. Bittner,et al.  Exciton dissociation dynamics in model donor-acceptor polymer heterojunctions. I. Energetics and spectra. , 2005, The Journal of chemical physics.

[33]  G. Scholes,et al.  Photon-echo studies of collective absorption and dynamic localization of excitation in conjugated polymers and oligomers , 2005 .

[34]  S. Forrest,et al.  Independent control of bulk and interfacial morphologies of small molecular weight organic heterojunction solar cells. , 2012, Nano letters.

[35]  Adam P. Willard,et al.  Hot charge-transfer excitons set the time limit for charge separation at donor/acceptor interfaces in organic photovoltaics. , 2013, Nature materials.

[36]  Stephen R. Forrest,et al.  Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films , 2003, Nature.

[37]  Marlan O Scully,et al.  Quantum photocell: using quantum coherence to reduce radiative recombination and increase efficiency. , 2010, Physical review letters.

[38]  Javier Prior,et al.  The role of non-equilibrium vibrational structures in electronic coherence and recoherence in pigment–protein complexes , 2013, Nature Physics.

[39]  G. Scholes.  Quantum-Coherent Electronic Energy Transfer: Did Nature Think of It First? , 2010 .

[40]  E. Bittner,et al.  Electroluminescence yield in donor-acceptor copolymers and diblock polymers: A comparative theoretical study , 2004 .

[41]  Ryan D. Pensack,et al.  Influence of Acceptor Structure on Barriers to Charge Separation in Organic Photovoltaic Materials , 2012 .

[42]  Ryogo Kubo,et al.  STOCHASTIC LIOUVILLE EQUATIONS , 1963 .

[43]  E. Bittner,et al.  Photoconductivity and current producing states in molecular semiconductors. , 2005, The Journal of chemical physics.

[44]  Time-convolutionless master equation for mesoscopic electron-phonon systems. , 2006, The Journal of chemical physics.

[45]  C. Sheng,et al.  Photoexcitation dynamics in polythiophene/fullerene blends for photovoltaic applications , 2012 .

[46]  E. Bittner,et al.  Energy relaxation dynamics and universal scaling laws in organic light-emitting diodes , 2002, cond-mat/0206015.

[47]  Exciton dynamics in disordered poly(p-phenylenevinylene). 1. Ultrafast interconversion and dynamical localization. , 2012, The journal of physical chemistry. A.

[48]  Jenny Clark,et al.  Ultrafast Long-Range Charge Separation in Organic Semiconductor Photovoltaic Diodes , 2014, Science.

[49]  J. Grey,et al.  Understanding Morphology-Dependent Polymer Aggregation Properties and Photocurrent Generation in Polythiophene/Fullerene Solar Cells of Variable Compositions , 2010 .

[50]  Dmitri V. Voronine,et al.  Photosynthetic reaction center as a quantum heat engine , 2013, Proceedings of the National Academy of Sciences.