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Non-Hermitian two-dimensional photonic crystal flat lens

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 نشر من قبل Jianjun Liu
 تاريخ النشر 2019
  مجال البحث فيزياء
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In this paper, a non-Hermitian two-dimensional photonic crystal flat lens is proposed. The negative refraction of the second band of photonic crystal is utilized to realize super-resolution imaging of the point source. Based on the principles of non-Hermitian systems, a negative imaginary part is introduced into the imaging frequency, in which case the imaging intensity and resolution are improved. The results indicate that the non-Hermitian system provides a new method to improve the imaging performance of the photonic crystal lens.

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