Abstract-Graphene Terahertz Modulators by Ionic Liquid Gating

1. Yang Wu^1,2, 
2. Chan La-o-vorakiat^3,4,
3. Xuepeng Qiu⁵, 
4. Jingbo Liu⁶, 
5. Praveen Deorani⁵, 
6. Karan Banerjee⁵, 
7. Jaesung Son⁵, 
8. Yuanfu Chen⁶, 
9. Elbert E. M. Chia^4,*and
10. Hyunsoo Yang^1,2,*

Article first published online: 3 FEB 2015

http://onlinelibrary.wiley.com/doi/10.1002/adma.201405251/abstract;jsessionid=4D3B95BDF171BDBF815E1504D6336819.f03t03?deniedAccessCustomisedMessage=&userIsAuthenticated=false

DOI: 10.1002/adma.201405251

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Excellent-performance terahertz (THz) modulators based on graphene/ionic liquid/graphene sandwich structures are demonstrated. The modulation covers a broadband frequency range from 0.1 to 2.5 THz with a modulation depth of up to 99% by applying a small gate voltage of 3 V. The outstanding performance of the proposed devices is due to the conical band structure of the graphene and the powerful gating effect of the ionic liquid in proximity to the graphene.