Microcomb-referenced photonic stabilization of resonant tunneling diode terahertz oscillators

Miezel Talara; Yu Tokizane; Tatsunoshin Mori; Ryota Shikata; Masayuki Higaki; Eiji Hase; Isao Morohashi; Safumi Suzuki; Naoya Kuse; Takeshi Yasui

arXiv · 2512.22752

Microcomb-referenced photonic stabilization of resonant tunneling diode terahertz oscillators

Miezel Talara·Yu Tokizane·Tatsunoshin Mori·Ryota Shikata·Masayuki Higaki·Eiji Hase·Isao Morohashi·Safumi Suzuki·Naoya Kuse·Takeshi Yasui

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Abstract

We demonstrate a compact stabilization scheme for terahertz (THz) sources by exploiting the complementary advantages of microresonator-based optical frequency combs (microcombs) and resonant tunneling diodes (RTDs). A microcomb-driven photomixing THz signal is employed as the master for injection locking of an RTD, enabling faithful transfer of the microcomb stability into the RTD. Using this approach, the free-running RTD linewidth of 50 MHz was narrowed to 165 Hz, while the single-sideband phase noise reached -80 dBc/Hz at a 10 kHz offset with a locking range of 80 MHz. Compared with conventional electronic frequency multiplier or fiber-comb-based schemes, this method avoids high-order frequency multiplication and associated noise penalties, offering a compact and practical alternative. The dual functionality of linewidth narrowing and power scalability highlights the potential of microcomb-assisted injection locking as a route toward chip-scale, spectrally pure THz sources for beyond-5G/6G wireless communication and radar, with prospects for future extension to time-frequency metrology and precision sensing.

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Miezel Talara, Yu Tokizane, Tatsunoshin Mori, Ryota Shikata, Masayuki Higaki, Eiji Hase, Isao Morohashi, Safumi Suzuki, Naoya Kuse, Takeshi Yasui. 2025-12-28. Microcomb-referenced photonic stabilization of resonant tunneling diode terahertz oscillators. https://arxiv.org/abs/2512.22752

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