Graphene based terahertz phase modulators

被引：91

作者：

Kakenov, N. ^{[1
]}

Ergoktas, M. S. ^{[2
,3
]}

Balci, O. ^{[1
]}

Kocabas, C. ^{[1
,2
,3
]}

机构：

[1] Bilkent Univ, Dept Phys, TR-06800 Ankara, Turkey

[2] Univ Manchester, Sch Mat, Oxford Rd, Manchester M13 9PL, Lancs, England

[3] Univ Manchester, Natl Graphene Inst, Oxford Rd, Manchester M13 9PL, Lancs, England

来源：

2D MATERIALS | 2018年 / 5卷 / 03期

基金：

英国工程与自然科学研究理事会; 欧洲研究理事会;

关键词：

terahertz phase; graphene; quarter wave surface; electrolyte gating; tunable surface impedance; gradient phase surface; SPATIAL LIGHT MODULATORS; METAMATERIALS; SHIFTER;

D O I：

10.1088/2053-1583/aabfaa

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Electrical control of amplitude and phase of terahertz radiation (THz) is the key technological challenge for high resolution and noninvasive THz imaging. The lack of active materials and devices hinders the realization of these imaging systems. Here, we demonstrate an efficient terahertz phase and amplitude modulation using electrically tunable graphene devices. Our device structure consists of electrolyte-gated graphene placed at quarter wavelength distance from a reflecting metallic surface. In this geometry, graphene operates as a tunable impedance surface which yields electrically controlled reflection phase. Terahertz time domain reflection spectroscopy reveals the voltage controlled phase modulation of pi and the reflection modulation of 50 dB. To show the promises of our approach, we demonstrate a multipixel phase modulator array which operates as a gradient impedance surface.

引用

页数：8

共 31 条

[1] Electrically switchable metadevices via graphene [J].