A compact and low-driving-voltage silicon electro-absorption modulator utilizing a Schottky diode operating up to 13.2 GHz in C-band. (9th November 2020)

• Record Type: Journal Article
• Authors: Jeong, Uiseok; Kim, Kwangwoong; Lee, Kyungwoon; Park, Jung Ho
• Is Part Of: Japanese journal of applied physics. Volume 59:Number 12(2020)
• Publication Date: 2020-11-09
• Subjects: Silicon modulator -- Electro-absorption -- Schottky diode -- SOI; Physics -- Periodicals; 621.05
• DOI: 10.35848/1347-4065/abc39f
• Languages: English
• ISSNs: 0021-4922

Abstract

Abstract: This paper demonstrates a 1 Vpp low-driving-voltage silicon electro-absorption modulator (EAM) utilizing a Schottky diode. Optical modulation using a Schottky diode was achieved through the intensity change of the guiding light due to free-carrier absorption in the semiconductor to change its absorption coefficient, not through conventional interference effects. The proposed EAM consists of a lateral metal–semiconductor junction that helps maximize free-carrier injection and extraction through a Schottky contact on rib waveguide. In order to achieve high-speed operation, traveling-wave type electrodes were designed. The fabricated EAM demonstrates a broad operational wavelength range of 50 nm for C-band with a uniform extinction ratio (ER) of 3.9 dB, even for a compact modulation length of 25 μ m with a driving voltage of 1 Vpp . Also, the traveling-wave type electrodes enabled the modulator to operate at up to 26 GHz with 13.2 GHz of 3 dB electro-optic bandwidth experimentally.