中国物理B ›› 2020, Vol. 29 ›› Issue (6): 67801-067801.doi: 10.1088/1674-1056/ab8a3c
所属专题： SPECIAL TOPIC — Topological 2D materials
• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇 下一篇
Acoustic plasmonics of Au grating/Bi2Se3 thin film/sapphirehybrid structures
Weiwu Li(李伟武), Konstantin Riegel, Chuanpu Liu(刘传普), Alexey Taskin, Yoichi Ando, Zhimin Liao(廖志敏), Martin Dressel, Yuan Yan(严缘)
- 1 Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany;
2 State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China;
3 Physics Institute II, University of Cologne, 50937 Köln, Germany;
4 Physikalisches Institut der Universität Würzburg, 97074 Würzburg, Germany;
5 Institute for Topological Insulators, 97074 Wurzburg, Germany
Acoustic plasmonics of Au grating/Bi2Se3 thin film/sapphirehybrid structures
Weiwu Li(李伟武)1, Konstantin Riegel1, Chuanpu Liu(刘传普)2, Alexey Taskin3, Yoichi Ando3, Zhimin Liao(廖志敏)2, Martin Dressel1, Yuan Yan(严缘)1,4,5
- 1 Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany;
2 State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China;
3 Physics Institute II, University of Cologne, 50937 Köln, Germany;
4 Physikalisches Institut der Universität Würzburg, 97074 Würzburg, Germany;
5 Institute for Topological Insulators, 97074 Wurzburg, Germany
摘要： The surface plasmon polaritons of the topological insulator Bi2Se3 can be excited by using etched grating or grave structures to compensate the wave vector mismatch of the incident photon and plasmon. Here, we demonstrate novel gold grating/Bi2Se3 thin film/sapphire hybrid structures, which allow the excitation of surface plasmon polaritons propagating through nondestructive Bi2Se3 thin film with the help of gold diffractive gratings. Utilizing periodic Au surface structures, the momentum can be matched and the normal-incidence infrared reflectance spectra exhibit pronounced dips. When the width of the gold grating W (with a periodicity 2W) increases from 400 nm to 1500 nm, the resonant frequencies are tuned from about 7000 cm-1 to 2500 cm-1. In contrast to the expected √q dispersion for both massive and massless fermions, where q～π/W is the wave vector, we observe a sound-like linear dispersion even at room temperature. This surface plasmon polaritons with linear dispersion are attributed to the unique noninvasive fabrication method and high mobility of topological surface electrons. This novel structure provides a promising application of Dirac plasmonics.
中图分类号: (Optical properties of surfaces)
- 78.68.+m