Coherent perfect absorption (CPA) is realized in metasurfaces composed of crossed vertical bulk Dirac semimetal (BDS) stripes and ${{\rm SiO}_2}$. Under the illumination of two counter-propagating coherent beams, the coherent absorption is continuously controlled from almost 0 (approximately ${6.2} \times {{10}^{- 5}}$) to 99.97% by changing the beams’ relative phase, which gives a modulation depth of about ${1.6} \times {{10}^4}$. Furthermore, the coherent absorption can be controlled substantially by varying the relative intensity, the Fermi energy of BDS, and the structural parameters of the metasurfaces. Further research shows that the metasurface has broadband angular selectivity: CPA frequency splits into TE and TM polarization bands under oblique incidence. Our results provide an effective way to manipulate the interaction of light and BDS, and there may be potential applications in coherent detectors and optical modulators.

中文翻译：

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基于块狄拉克半金属的动态可调相干完美吸收

相干完美吸收（CPA）在由垂直垂直散装Dirac半金属（BDS）条纹和$ {{\ rm SiO} _2} $组成的超表面上实现。在两个反向传播的相干光束的照射下，通过改变光束的相对相位，相干吸收从近乎0（约$ {6.2} \乘以{{10} ^ {-5}} $的连续控制到99.97％ ，其调制深度约为$ {1.6} \ times {{10} ^ 4} $。此外，基本上可以通过改变相对强度，BDS的费米能和超表面的结构参数来控制相干吸收。进一步的研究表明，超颖表面具有宽带角度选择性：在倾斜入射下，CPA频率分为TE和TM极化带。我们的结果提供了一种有效的方法来操纵光与BDS的相互作用，并且在相干探测器和光学调制器中可能有潜在的应用。