Metasurfaces, the two-dimensional analog of metamaterials, have exhibited unprecedented optical and thermal properties including super-Planckian thermal radiation.~Asymmetrically patterning two-dimensional materials have been proposed recently to excite additional surface hyperbolic modes, which could enhance radiative energy transport.~In present study, we further look into the effect of symmetric patterns.~The graphene metasurfaces are selected as an example to present the improving role of symmetric patterning in radiative heat flux.~Fluctuational electrodynamics that incorporates scattering matrix theory with rigorous coupled-wave analysis is employed to exactly calculate the near-field heat flux.~It is shown that the radiative heat flux between graphene metasurfaces with square patterns performs a maximum 35-fold enhancement compared with sheets counterpart, far exceeding the performance based on asymmetric patterning.}~The enhanced heat flux is dominated by a different mechanism through excitation and redshift of graphene surface plasmon polaritons with high in-plane wavevector.~The effects of substrate, vacuum gap distance and surface geometry parameters between the two metasurfaces with symmetric pattern are also investigated.}~This work opens an alternative route to enhance and modulate the metasurface based radiative heat transfer for efficient thermal energy management at micro/nanoscales.

中文翻译：

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具有对称纳米图案的石墨烯超表面之间增强的近场辐射传热

超材料是超材料的二维模拟物，具有超前的光学和热特性，包括超普朗克热辐射。〜最近提出了对二维材料进行不对称构图以激发附加的表面双曲模式，从而增强辐射能的传输。在本研究中，我们将进一步研究对称图案的影响。〜以石墨烯超表面为例来说明对称图案在辐射热通量中的改进作用。〜将散射矩阵理论与严格的耦合波分析相结合的涨落电动力学用于精确计算近场热通量。〜显示出，具有正方形图案的石墨烯超表面之间的辐射热通量比薄片对应物具有最大35倍的增强，远远超过了基于不对称图案形成的性能。}〜增强的热通量是通过激发的不同机制控制的高平面内波矢的石墨烯表面等离子体激元极化子和红移。〜还研究了衬底，真空间隙距离和两个具有对称图案的超颖表面之间的表面几何参数的影响。}〜这项工作为增强和调制开辟了一条替代途径基于超表面的辐射传热，可有效实现微米/纳米尺度的热能管理。}〜通过激发和红移具有高平面内波矢量的石墨烯表面等离激元极化子，增强的热通量由不同的机制控制。〜衬底，真空间隙距离和对称图案的两个超表面之间的表面几何参数的影响}〜这项工作为增强和调制基于超表面的辐射传热开辟了一条替代途径，以便在微米/纳米尺度上进行有效的热能管理。}〜通过激发和红移具有高平面内波矢量的石墨烯表面等离激元极化子，增强的热通量由不同的机制控制。〜衬底，真空间隙距离和对称图案的两个超表面之间的表面几何参数的影响}〜这项工作为增强和调制基于超表面的辐射传热开辟了一条替代途径，以便在微米/纳米尺度上进行有效的热能管理。}〜这项工作为增强和调制基于超表面的辐射传热开辟了一条替代途径，以便在微米/纳米尺度上进行有效的热能管理。}〜这项工作为增强和调制基于超表面的辐射传热开辟了一条替代途径，以便在微米/纳米尺度上进行有效的热能管理。