We present a continuously tunable optical frequency comb generator (OFCG), with comb lines spanning over 3.8 THz which, to the best of our knowledge, is the widest span yet reported for a single-phase modulator OFCG system. The line spacing, exactly determined by a microwave reference, can be continuously tuned and, by heterodyning two lines, enables the generation of a continuously tunable electrical signal from 122.5 GHz to $>2.7\mathrm{THz}$. The composite noise of the heterodyne between two lines has been measured up to a record frequency of 300 GHz and is $-75\mathrm{dBc}/\mathrm{Hz}$ at 10 kHz offset at 300 GHz, limited by the multiplied phase noise of the reference synthesizer.

中文翻译：

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光梳，用于产生从122.5 GHz到> 2.7 THz的连续可调的相干THz信号

我们提出了一种连续可调的光频率梳状发生器（OFCG），其梳状线的跨度超过3.8 THz，据我们所知，这是单相调制器OFCG系统迄今所报道的最宽的跨度。可以连续调谐由微波参考精确确定的线间距，并且通过使两条线异质化，可以生成从122.5 GHz到122.5 GHz的连续可调电信号。$>2.7\mathrm{太赫兹}$。测量了两条线之间的外差的复合噪声，最高记录频率为300 GHz，并且$-75\mathrm{分贝}/\mathrm{赫兹}$ 频率在300 GHz时的10 kHz偏移处受到参考合成器相乘噪声的限制。