Ultra-Compact Bidirectional Terahertz Switch Based on Resonance in Graphene Ring and Plate

Document Type : Articles


1 Department of Electrical Engineering, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran

2 Department of Electrical Engineering, Science and Research Branch, Islamic Azad University, Tehran 1477893855, Iran

3 School of electrical and computer engneering,tarbiat modares university

4 School of Electrical and Computer Engineering, Tarbiat Modares University


In this paper, we present a switch based on coupling and resonance in the
graphene plate and rings operating at 10 THz. This structure consists of several layers of
Hexagonal Boron Nitride (hBN), SiO2 and P+Si, such that graphene plates and rings are
inside the hBN layer. The terahertz wave is incident from the upper part of the switch
and Surface Plasmons (SPs) are excited by the grating in the structure on the graphene
plate beneath the nano-aperture and moves towards the ports available on the left and
right of the switch. At first, at the certain applied voltage, the SPs cross the left port and
this port is ON. With the increase in voltage and the change in the chemical potential,
switching occurs and the SPs exit from the right and this port is ON while the left port
turns OFF. The extinction ratio in this structure is 18dB and the size of the structure is
1μm. Aforementioned benefits make this switch the best choice for using in integrated
optical circuits.