Modeling and Analysis of Device Orientation, Analog and Digital Performance of Electrode Design for High Speed Electro-Optic Modulator

Abstract

Electro-optic modulators (EOMs) are crucial devices for modern communication enabling high bandwidth optical communication links. Traveling wave electrodes are used to obtain high-speed modulation in these EOMs. We present the electrode design and analysis along with the study of effects of changing orientation on device performance for a thin-film lithium niobate tunable Mach–Zehnder interferometer (MZI) that offers sub-THz bandwidth operations. High velocity and impedance matching with low RF attenuation, high third-order SFDR (∼121 dB/Hz2/3) and a low half-wave voltage length product (1.74 V.cm) have been achieved for a bandwidth of 136 GHz. High-speed digital modulation using multi-level signal formats (PAM-2, QAM-4 and QAM-16) with low BER for 400 Gbps data has been demonstrated to assess the digital performance of the device.

Review of advanced progress of χ2-based all-optical devices on thin-film lithium niobate

“…The step poling period introduced the rich reciprocal vectors match that led to the tunability of the wavelength. However, it is worth noting that the second harmonic was generated from 1550 nm to 1660 nm (110 nm) of the pump despite the cost of a low conversion efficiency of 9.6%=W • cm 2 . In addition to the step-chirped waveguide, a high wavelength tunability could also be achieved by regulating the refractive index at different temperatures [49] .…”

“…In addition to the step-chirped waveguide, a high wavelength tunability could also be achieved by regulating the refractive index at different temperatures [49] . This capability of temperature sensitivity promotes the high tunability in the PM of the wavelength with a tuning slope of 0.84 nm/K at the cost of a low conversion efficiency under 22.2%=W • cm 2 .…”

“…Integrated optics with cheap, high efficiency, low-pump, and large-scale integration will prevail in the future. This includes various functional integrated optical devices on a single substrate, which show significant potential in applications in many optical fields, such as optical interconnection [1] , optical communication [2,3] , quantum computing [4,5] , optical neural network computing [6] , and sensing systems [7] . In integrated optics, the nonlinear property provides novel applications with its extreme spectral broadening and optical signal processing capability.…”

A Comprehensive Approach to LNOI Electro-Optic Modulator Design and Performances Optimizing

“…Although III-V materials effectively address bandwidth limitations and cater to the demands of high-speed communication and modulation, their performance are restricted by significant optical losses and high linearity requirements. By contrast, lithium niobate has garnered significant attention in photonics, owing to its broader optical transparency window, relatively higher refractive index, nonlinear coefficient, and substantial electro-optic coefficient [13,14]. For traditional bulk LN modulators, the relatively small refractive index difference between the core and cladding layers results in a weaker confinement of the optical mode field and higher power consumption, thereby constraining the performance of the modulator.…”