Design and analysis of iii-nitride nanowire-based electroabsorption modulators for on-chip optical communication

Abstract

The dramatic improvement in modern short-distance and long-distance optical telecommunication network performance is a result of high-speed photonic and optoelectronic devices. Advanced material growth and device fabrication technologies have impressively matured, and the development of photonic and optoelectronic integrated circuits (OEICs) has engaged considerable efforts to achieve well beyond conventional perspectives. This innovation is critical to the development of improved on-chip and off-chip high-speed optical communication systems that can transmit data more efficiently and at higher speeds. The proposed nanowire-based electroabsorption modulator is designed to modulate signals visible to the NIR region. The absorption characteristics dependent on incident light wavelength and electric field were evaluated through a self-consistent numerical method. Output characteristics of a nanowire system are calculated at the wavelength of blue, green, and NIR regions. The study's results indicate that optimal performance can be attained by adjusting the electric field from 239 V/µm to 326 V/µm, which corresponds to the 'ON' and 'OFF' states at a wavelength of 430 nm, 460 nm, 530 nm, and 830 nm. For system-level integration, an optical interconnect system is designed to evaluate different figures of merit (FOM), such as bit error rate (BER), extinction ratio (ER), and quality factor (Q-factor). The highest modulation speed obtained is 90 Gbps at an operating wavelength of 460 nm, under conditions of 50 μW input power, a cutoff bit error rate of 〖10〗^(-9) and a path loss of 1 dB/mm. Conversely, at an operating wavelength of 830 nm, the modulation speed is the lowest, recorded at 5 Gbps under the same system parameters. The 460 nm wavelength also exhibits superior performance in terms of extinction ratio and quality factor, which are measured at 12.47 dB and 31.93, respectively. These results underscore the enhanced efficiency and effectiveness of the 460 nm wavelength for high-speed optical communication applications. This work will also open the door to the development of high-performance nanowire-based electroabsorption modulators, enabling the implementation of efficient and reliable optical communication systems for diverse application.