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Related papers: Theory of excited state absorptions in phenylene-b…

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In a recently performed experiment Korovyanko et al [Phys. Rev. B 67, 035114 (2003)] have measured the photo-induced absorption (PA) spectrum of phenyl-disubstituted polyacetylenes (PDPA) from 1$B_{u}$ and 2$A_{g}$ excited states. In…

Materials Science · Physics 2010-01-14 Priya Sony , Alok Shukla

In this paper we present results of large-scale correlated calculations of triplet photoinduced absorption (PA) spectrum of oligomers of poly-(para)phenylenevinylene (PPV) containing up to five phenyl rings. In particular, the high-energy…

Condensed Matter · Physics 2010-01-14 Alok Shukla

We extend Mulliken's theory of ground state charge transfer in a donor-acceptor complex to excited state charge transfer between pairs of identical $\pi$-conjugated oligomers, one of which is in the optically excited state and the other in…

Materials Science · Physics 2009-05-18 D. Psiachos , S. Mazumdar

In this paper, we report theoretical calculations of the photo-induced absorption (PA) spectrum of naphthalene and anthracene, with the aim of understanding those excited states, which are invisible in the linear optical absorption. The…

Materials Science · Physics 2009-08-05 Priya Sony , Alok Shukla

The two state molecular orbital (2-MO) model of the phenyl based semiconductors is used to calculate the low-lying spectra of the Ag and Bu states of poly(para-phenylene) (PPP). The model parameters are determined by fitting its predictions…

Condensed Matter · Physics 2009-10-31 W. Barford , R. J. Bursill , M. Yu. Lavrentiev

The Pariser-Parr-Pople model of pi-conjugated electrons is solved by the density matrix renormalization group method for the light emitting polymer, poly(para-phenylene vinylene). The energies of the primary excited states are calculated.…

Strongly Correlated Electrons · Physics 2007-05-23 Robert J. Bursill , William Barford

A two state (2-MO) model for the low-lying long axis-polarised excitations of poly(p-phenylene) oligomers and polymers is developed. First we derive such a model from the underlying Pariser-Parr-Pople (P-P-P) model of pi-conjugated systems.…

Condensed Matter · Physics 2009-10-31 R. J. Bursill , W. Barford , H. Daly

We report the symmetrized density matrix renormalization group (DMRG) study of neutral and doped oligomers of PPP system within an extended Hubbard model. Model parameters are determined by comparing the existing results for interacting…

Condensed Matter · Physics 2007-05-23 Y. Anusooya , Swapan K. Pati , S. Ramasesha

We present a theory of the electronic structure and photophysics of 1:1 blends of derivatives of polyparaphenylenevinylene and fullerenes. Within the same Coulomb-correlated Hamiltonian applied previously to interacting chains of…

Strongly Correlated Electrons · Physics 2015-05-13 K. Aryanpour , D. Psiachos , S. Mazumdar

Electron-electron interactions in general lead to both ground state and excited state confinement. We show, however, that in phenyl-substituted polyacetylenes electron-electron interactions cause enhanced delocalization of quasiparticles in…

Strongly Correlated Electrons · Physics 2009-10-31 Haranath Ghosh , Alok Shukla , Sumit Mazumdar

There is an enormous potential in applying conjugated polymers in novel organic opto-electronic devices such as light emitting diodes and solar cells. Although prototypes and first products exist, a comprehensive understanding of the…

Electronic excitations in dilute solutions of poly para phenylene ethynylene (poly-PPE) are studied using a QM/MM approach combining many-body Green's functions theory within the $GW$ approximation and the Bethe-Salpeter equation with…

Materials Science · Physics 2016-08-24 Behnaz Bagheri , Mikko Karttunen , Björn Baumeier

A density matrix renormalisation group scheme is developed, allowing for the first time essentially exact numerical solutions for the important excited states of a realistic semi-empirical model for oligo-phenylenes. By monitoring the…

Condensed Matter · Physics 2009-11-07 Robert J. Bursill , W. Barford

We report pressure-dependent transient picosecond and continuous-wave photomodulation studies of disordered and ordered films of 2-methoxy-5-(2-ethylhexyloxy) poly(para-phenylenevinylene). Photoinduced absorption (PA) bands in the…

Strongly Correlated Electrons · Physics 2015-05-20 K. Aryanpour , C. -X. Sheng , E. Olejnik , B. Pandit , D. Psiachos , S. Mazumdar , Z. V. Vardeny

We present density matrix renormalisation group calculations of the Pariser- Parr-Pople-Peierls model of linear polyenes within the adiabatic approximation. We calculate the vertical and relaxed transition energies, and relaxed geometries…

Condensed Matter · Physics 2009-11-07 William Barford , Robert J. Bursill , Mikhail Yu Lavrentiev

We are the first to show with clear experimental results that photons that have energy lower than the transition energy between quantum dots states and valance band can still contribute greatly to the photocurrent via both one-photon…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 Tian Li , Mario Dagenais

In this paper, we present a theoretical study of the nonlinear optical response of the newly discovered conjugated polymer poly(diphenyl)polyacetylene (PDPA). In particular, we compute the third-order nonlinear susceptibility corresponding…

Mesoscale and Nanoscale Physics · Physics 2010-01-14 Alok Shukla

Many-body perturbation theory at the $G_0W_0$ level is employed to study the electronic properties of poly(\emph{para}-phenylene) (PPP) on graphene. Analysis of the charge density and the electrostatic potential shows that the…

Materials Science · Physics 2012-08-17 Peter Puschnig , Peiman Amiri , Claudia Draxl

Spatial configurations of randomly charged polymers, known as polyampholytes (PAs), are very sensitive to the overall excess charge Q. Analytical arguments, supported by Monte Carlo simulations and exact enumeration studies, lead to the…

Condensed Matter · Physics 2007-11-28 Yacov Kantor , Mehran Kardar

An excitonic method proper to study conjugated oligomers and polymers is described and its applicability tested on the ground state and first excited states of trans-polyacetylene, taken as a model. From the Pariser-Parr-Pople Hamiltonian,…

Condensed Matter · Physics 2009-10-31 S. Pleutin , J. L. Fave
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