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Employing a Narrow-Band-Gap Mediator in Ternary Solar Cells for Enhanced Photovoltaic Performance.
Ternary organic solar cells (OSCs) provide a convenient and effective means to further improve the power conversion efficiency (PCE) of binary ones via composition control. However, the role of the third component remains to be explored in specific binary systems. Herein, we report ternary blend solar cells by adding the narrow-band-gap donor PCE10 as the mediator into the PBDB-T:IDTT-T binary blend system. The extended absorption, efficient fluorescence resonance energy transfer, enhanced charge dissociation, and induced tighter molecular packing of the ternary blend films enhance the photovoltaic properties of devices and deliver a champion PCE of 10.73% with an impressively high open-circuit voltage (VOC) of 1.03 V. Good miscibility and similar molecular packing behavior of the components guarantee the desired morphology in the ternary blend films, leading to solar cell devices with over 10% PCEs at a range of compositions. Our results suggest that ternary systems with properly aligned energy levels and overlapping absorption among the components hold great promises to further enhance the performance of corresponding binary ones
Immunization for complex network based on the effective degree of vertex
The basic idea of many effective immunization strategies is first to rank the
importance of vertices according to the degrees of vertices and then remove the
vertices from highest importance to lowest until the network becomes
disconnected. Here we define the effective degrees of vertex, i.e., the number
of its connections linking to un-immunized nodes in current network during the
immunization procedure, to rank the importance of vertex, and modify these
strategies by using the effective degrees of vertices. Simulations on both the
scale-free network models with various degree correlations and two real
networks have revealed that the immunization strategies based on the effective
degrees are often more effective than those based on the degrees in the initial
network.Comment: 16 pages, 5 figure
Effective Hamiltonian approach to the quantum phase transitions in the extended Jaynes-Cummings model
The study of phase transitions in dissipative quantum systems based on the
Liouvillian is often hindered by the difficulty of constructing a time-local
master equation when the system-environment coupling is strong. To address this
issue, the complex discretization approximation for the environment is proposed
to study the quantum phase transition in the extended Jaynes-Cumming model with
an infinite number of boson modes. This approach yields a non-Hermitian
effective Hamiltonian that can be used to simulate the dynamics of the spin. It
is found that the ground state of this effective Hamiltonian determines the
spin dynamics in the single-excitation subspace. Depending on the opening of
the energy gap and the maximum population of excitations on the spin degree of
freedom, three distinct phases can be identified: fast decaying, localized, and
stretched dynamics of the spin. This approach can be extended to multiple
excitations, and similar dynamics were found in the double-excitation subspace,
indicating the robustness of the single-excitation phase.Comment: 12pages, published versio
Reduced dynamics with renormalization in solid-state charge qubit measurement
Quantum measurement will inevitably cause backaction on the measured system,
resulting in the well known dephasing and relaxation. In this report, in the
context of solid--state qubit measurement by a mesoscopic detector, we show
that an alternative backaction known as renormalization is important under some
circumstances. This effect is largely overlooked in the theory of quantum
measurement.Comment: 12 pages, 4 figure
Complex Discretization approximation for the full dynamics of system-environment quantum models
The method of discretization approximation for the environment in continuum
suffers from the recurrence, that makes the simulation of the open dynamics
inefficient. In order to tackle this problem, the discretization approximation
is generalized into the complex plane by introducing complex Gauss quadratures
in this paper. The resulting effective Hamiltonian is thus non-Hermitian due to
the dissipative dynamics of system. As illustrations, the open dynamics in two
exactly solvable models, dephasing model and the single-excitation open
dynamics in the generalized Aubry-Andr\'{e}-Harper model, is checked
respectively by the method. It is found that the recurrence can be compressed
greatly due to the occurrence of complex discrete modes in environment. Thus,
the open dynamics in the two models can be simulated in high efficiency and
precision.Comment: 13 pages. the statement has been improved and the references are
updated. Comments are welcom
Genome-wide linkage analysis for alcohol dependence: a comparison between single-nucleotide polymorphism and microsatellite marker assays
Both theoretical and applied studies have proven that the utility of single nucleotide polymorphism (SNP) markers in linkage analysis is more powerful and cost-effective than current microsatellite marker assays. Here we performed a whole-genome scan on 115 White, non-Hispanic families segregating for alcohol dependence, using one 10.3-cM microsatellite marker set and two SNP data sets (0.33-cM, 0.78-cM spacing). Two definitions of alcohol dependence (ALDX1 and ALDX2) were used. Our multipoint nonparametric linkage analysis found alcoholism was nominal linked to 12 genomic regions. The linkage peaks obtained by using the microsatellite marker set and the two SNP sets had a high degree of correspondence in general, but the microsatellite marker set was insufficient to detect some nominal linkage peaks. The presence of linkage disequilibrium between markers did not significantly affect the results. Across the entire genome, SNP datasets had a much higher average linkage information content (0.33 cM: 0.93, 0.78 cM: 0.91) than did microsatellite marker set (0.57). The linkage peaks obtained through two SNP datasets were very similar with some minor differences. We conclude that genome-wide linkage analysis by using approximately 5,000 SNP markers evenly distributed across the human genome is sufficient and might be more powerful than current 10-cM microsatellite marker assays
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