Interdigitated back contact silicon hetero-junction(IBC-SHJ) solar cells exhibit excellent performance owing to the IBC and SHJ structures.The front surface field(FSF) layer composed of electric field passivation and ...Interdigitated back contact silicon hetero-junction(IBC-SHJ) solar cells exhibit excellent performance owing to the IBC and SHJ structures.The front surface field(FSF) layer composed of electric field passivation and chemical passivation has been proved to play an important role in IBC-SHJ solar cells.The electric field passivated layer n^+-a-Si: H, an n-type Si alloy with carbon or oxygen in amorphous phase, is simulated in this study to investigate its effect on IBC-SHJ.It is indicated that the n^+-a-Si: H layer with wider band gap can reduce the light absorption on the front side efficaciously,which hinders the surface recombination of photo-generated carriers and thus contributes to the improvement of the short circuit current density Jsc.The highly doped n^+-a-Si: H can result in the remakable energy band bending, which makes it outstanding in the field passivation, while it makes little contribution to the chemical passivation.It is noteworthy that when the electric field intensity exceeds 1.3 × 10^5 V/cm, the efficiency decrease caused by the inferior chemical passivation is only 0.16%.In this study, the IBC-SHJ solar cell with a front n^+-a-Si: H field passivation layer is simulated, which shows the high efficiency of 26% in spite of the inferior chemical passivation on the front surface.展开更多
We study the near-field response of a shell nanocylinder pair, with its core filled by gain materials, using a two- dimensional finite-difference time-domain method. It is shown that the gain materials in the core of ...We study the near-field response of a shell nanocylinder pair, with its core filled by gain materials, using a two- dimensional finite-difference time-domain method. It is shown that the gain materials in the core of the cylinder can compensate for the intrinsic absorption of the metal shell, leading to local-field enhancement in the gap of the active pair. A linear dependence is found between the field enhancement and the gain coefficient at resonance. The detailed physics is studied by calculating the electrical-field distribution of the shell pair filled with different gain materials. The influence of the gap width and the shell thickness on the interaction of two adjacent active shell cylinders is also investigated.展开更多
Noble metal nanocavities have been widely demonstrated to possess great potential applications in nanooptics and nanophotonics due to their extraordinary localized surface plasmon resonance.However,most metal nanocrys...Noble metal nanocavities have been widely demonstrated to possess great potential applications in nanooptics and nanophotonics due to their extraordinary localized surface plasmon resonance.However,most metal nanocrystals synthesized by chemical methods often suffer from truncation with different degrees due to oxidation and dissolution of metal atoms at corner and edges.We investigate the influence of shape truncation on the plasmonic properties of single Ag nanowire on Au film nanocavity using the finite difference time domain method.When the Ag nanowire(the circumradius R_(2)=50 nm)is gradually truncated from pentagonal to circular geometry,the scattering peak position of the nanocavity shows prominent blue shift from 962 nm to 608 nm,suggesting a nonnegligible role of truncation on plasmonic properties.The electric field strength and charge distribution of the structure reveal the evolution from dipole mode to quadrupole mode.It is also found that the plasmon resonance wavelength is linearly dependent on the truncation ratio R_(1)/R_(2)(R_(1) is the inradius)and the modulation slope is also reliable to the size of Ag nanowire.Our observations could shed light on developing high-performance tunable optical nano-devices in future.展开更多
基金Project supported by the National Key Research Program of China(Grant Nos.2018YFB1500500 and 2018YFB1500200)the National Natural Science Foundation of China(Grant Nos.51602340,51702355,and 61674167)JKW Project,China(Grant No.31512060106)
文摘Interdigitated back contact silicon hetero-junction(IBC-SHJ) solar cells exhibit excellent performance owing to the IBC and SHJ structures.The front surface field(FSF) layer composed of electric field passivation and chemical passivation has been proved to play an important role in IBC-SHJ solar cells.The electric field passivated layer n^+-a-Si: H, an n-type Si alloy with carbon or oxygen in amorphous phase, is simulated in this study to investigate its effect on IBC-SHJ.It is indicated that the n^+-a-Si: H layer with wider band gap can reduce the light absorption on the front side efficaciously,which hinders the surface recombination of photo-generated carriers and thus contributes to the improvement of the short circuit current density Jsc.The highly doped n^+-a-Si: H can result in the remakable energy band bending, which makes it outstanding in the field passivation, while it makes little contribution to the chemical passivation.It is noteworthy that when the electric field intensity exceeds 1.3 × 10^5 V/cm, the efficiency decrease caused by the inferior chemical passivation is only 0.16%.In this study, the IBC-SHJ solar cell with a front n^+-a-Si: H field passivation layer is simulated, which shows the high efficiency of 26% in spite of the inferior chemical passivation on the front surface.
基金Project support by the National Natural Science Foundation of China (Grant Nos. 10975012 and 11074029)
文摘We study the near-field response of a shell nanocylinder pair, with its core filled by gain materials, using a two- dimensional finite-difference time-domain method. It is shown that the gain materials in the core of the cylinder can compensate for the intrinsic absorption of the metal shell, leading to local-field enhancement in the gap of the active pair. A linear dependence is found between the field enhancement and the gain coefficient at resonance. The detailed physics is studied by calculating the electrical-field distribution of the shell pair filled with different gain materials. The influence of the gap width and the shell thickness on the interaction of two adjacent active shell cylinders is also investigated.
基金the National Natural Science Foundation of China(Grant No.11604157)Nanjing University of Information Science&Technology(Grant No.2016206)。
文摘Noble metal nanocavities have been widely demonstrated to possess great potential applications in nanooptics and nanophotonics due to their extraordinary localized surface plasmon resonance.However,most metal nanocrystals synthesized by chemical methods often suffer from truncation with different degrees due to oxidation and dissolution of metal atoms at corner and edges.We investigate the influence of shape truncation on the plasmonic properties of single Ag nanowire on Au film nanocavity using the finite difference time domain method.When the Ag nanowire(the circumradius R_(2)=50 nm)is gradually truncated from pentagonal to circular geometry,the scattering peak position of the nanocavity shows prominent blue shift from 962 nm to 608 nm,suggesting a nonnegligible role of truncation on plasmonic properties.The electric field strength and charge distribution of the structure reveal the evolution from dipole mode to quadrupole mode.It is also found that the plasmon resonance wavelength is linearly dependent on the truncation ratio R_(1)/R_(2)(R_(1) is the inradius)and the modulation slope is also reliable to the size of Ag nanowire.Our observations could shed light on developing high-performance tunable optical nano-devices in future.
