title: Terahertz Modulator based on Metamaterials integrated with Metal-Semiconductor-Metal Varactors.
abstract: The terahertz (THz) band of the electromagnetic spectrum, with frequencies ranging from 300 GHz to 3 THz, has attracted wide interest in recent years owing to its potential applications in numerous areas. Significant progress has been made toward the development of devices capable of actively controlling terahertz waves; nonetheless, further advances in device functionality are necessary for employment of these devices in practical terahertz systems. Here, we demonstrate a low voltage, sharp switching terahertz modulator device based on metamaterials integrated with metal semiconductor metal (MSM) varactors, fabricated on an AlGaAs/InGaAs based heterostructure. By varying the applied voltage to the MSM-varactor located at the center of split ring resonator (SRR), the resonance frequency of the SRR-based metamaterial is altered. Upon varying the bias voltage from 0 V to 3 V, the resonance frequency exhibits a transition from 0.52 THz to 0.56 THz, resulting in a modulation depth of 45 percent with an insertion loss of 4.3 dB at 0.58 THz. This work demonstrates a new approach for realizing active terahertz devices with improved functionalities.
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Muhammad Tayyab
authors.initials: MT
authors.lastname: Nouman
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Hyun-Woong
authors.initials: HW
authors.lastname: Kim
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Woo
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Hwang
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Dongju
authors.initials: D
authors.lastname: Kim
authors.affiliation: School of Electrical Engineering and Computer Science, Gwangju Institute of Science and Technology, 1 Oryongdong Buk-gu, Gwangju 500-712, South Korea.
authors.forename: Jae-Hyung
authors.initials: JH
authors.lastname: Jang