石墨烯-六方氮化硼异质结构的古斯-汉欣位移调控

Control of Goos-Hanchen Shift Based on Graphene/Hexagonal Boron Nitride Heterostructure

利用传输矩阵法在红外波段实现了基于石墨烯-六方氮化硼(hBN)异质结构的古斯-汉欣(GH)位移的增强和调控。理论研究表明,由于hBN在红外波段产生洛伦兹共振现象,当使用波长为12.20μm的横磁偏振光入射时,通过调节石墨烯的费米能级或石墨烯层数可以有效增强异质结构的GH位移量。当费米能级为0.2 eV时,仅使用单层石墨烯作用该异质结构即可达到80.97λ的GH位移量;此外,GH位移随hBN厚度的变化规律表现出与hBN介电常数相似的特征。当hBN厚度在1.53μm附近变化时,可以实现-150λ~150λ范围内的正向或负向GH位移的灵活切换。这些研究结果有助于设计新型高灵敏度红外光学传感器。

In this study,the transfer matrix method is used to enhance and regulate Goos-H?nchen(GH)shift based on graphene/hexagonal boron nitride(hBN)heterostructure in the infrared band.Theoretical research demonstrates that when the transverse magnetic polarized light with 12.20μm wavelength is incident,hBN heterostructure GH shift can be effectively improved by adjusting the Fermi level of graphene or the number of graphene layer.This phenomenon is attributed to the Lorentz resonance phenomenon in the infrared band of hBN.For 0.2 eV Fermi energy,GH shift of 80.97λcan be achieved using a single layer of graphene as the heterostructure.Moreover,the law of GH shift varying with the hBN thickness exhibits the same as that with the hBN dielectric constant.Notably,when the hBN thickness changes around 1.53μm,the positive and negative variations in GH shift can be flexibly switched in the range of-150λ-150λ.Furthermore,these findings are helpful in designing new high-sensitivity infrared optical sensors.