Breaking voltage–bandwidth limits in integrated lithium niobate modulators using micro-structured electrodes

By P. Kharel, C. Reimer, K. Luke, Lingyan He, Mian Zhang. 2020

290 citations recorded by the source corpus.

Electro-optic modulators with low voltage and large bandwidth are crucial for both analog and digital communications. Recently, thin-film lithium niobate modulators have enable dramatic performance improvements by reducing the required modulation voltage while maintaining high bandwidths. However, the reduced electrode gaps in such modulators leads to significantly higher microwave losses, which limit electro-optic performance at high frequencies. Here we overcome this limitation and achieve a record combination of low RF half-wave voltage of 1.3 V while maintaining electro-optic response with 1.8-dB roll-off at 50 GHz. This demonstration represents a significant improvement in voltage-bandwidth limit, one that is comparable to that achieved when switching from legacy bulk to thin-film lithium niobate modulators. Leveraging the low-loss electrode geometry, we show that sub-volt modulators with $>$ 100 GHz bandwidth can be enabled.

Subfields: Atomic and Molecular Physics, and Optics, Electrical and Electronic Engineering

View Paper: https://www.semanticscholar.org/paper/56ea5778b5b3c7ff2b0ae6e409cdffc67d9ed631

Citations in the corpus

• Integrated electro-optics on thin-film lithium niobate (2024, unknown): “One drawback is that the capacitive loading reduces the microwave phase velocity, which requires a low-index handle wafer (such as quartz 52 ) or undercuts in the high-index Si substrate 82 to maintain velocity matching.”