Lithium niobite membrane QPSK light modulator and manufacturing method thereof

Abstract

The invention discloses a lithium niobite membrane QPSK light modulator and a manufacturing method thereof. The light modulator includes a quartz base wafer, lithium niobite membrane, an optical waveguide, a metal membrane electrode and a metallically-packed pipe shell. The method has the following advantages that 1, the length of the crooked waveguide and a traveling wave electrode is shortened,a direct current offset compensation electrode is removed, and the miniaturization of the lithium niobite QPSK light modulator is achieved; 2, a quartz material with a low dielectric constant is adopted as the base wafer of a lithium niobite single crystal membrane, great matching of the microwave refractive index and the optical wave refractive index is achieved, and the modulation bandwidth of the lithium niobite QPSK light modulator is increased; 3, since the direct current offset compensation electrode is removed, the signal processing complexity of the lithium niobite QPSK light modulatoris lowered; 4, the utilization rate of a lithium niobite membrane wafer is increased, and the manufacturing cost of the lithium niobite QPSK light modulator is reduced.

Description

technical field [0001] The invention relates to technical fields such as ultra-high-speed / ultra-long-distance optical communication, coherent optical communication, and other optical fiber communication technologies, and in particular relates to a lithium niobate thin-film QPSK optical modulator and a manufacturing method thereof. Background technique [0002] Quadrature phase-shift keying (QPSK) technology has become an optical transmission technology in recent years, especially in dense wavelength division multiplexing (DWDM) systems, due to its advantages of high spectral utilization, high signal-to-noise ratio and high dispersion tolerance. A widely used modulation format for bit rate transmission. [0003] The development of lithium niobate MZ modulators based on the Pockels electro-optic effect of lithium niobate crystals played a very important role in the early development of optical fiber communication networks. Although optical transmitters using directly modulate...

AI Technical Summary

Problems solved by technology

[0008] 3) The use of DC bias electrodes: In order to achieve high modulation bandwidth in existing lithium niobate QPSK optical modulators, a silicon dioxide buffer layer must be used to achieve a good match between the microwave refractive index and the optical wave refractive index. However, the silicon dioxide buffer layer The introduction of the layer also brings about the serious problem of DC bias drift, leading to the lithium niobate QPSK optical modulator must use integrated photodetectors and DC bias electrodes to compensate for DC bias drift in real time, ensuring that the optical modulator is always at the optimum best working point

The use of DC bias electrodes undoubtedly increases the length of the existing lithium niobate QPSK optical modulator

[0009] In addition, the long device size of the existing lithium niobate QPSK optical modulator also has the problem of low utilization rate of lithium niobate wafers in the chip manufacturing process, resulting in a lot of waste of lithium niobate wafers and increasing Manufacturing cost of existing lithium niobate QPSK optical modulators

Images