Diddams S A, Kirchner M, Fortier T, Braje D, Weiner A M, Hollberg L
Time and Frequency Division, National Institute of Standards and Technology, Boulder, CO 80305, USA.
Opt Express. 2009 Mar 2;17(5):3331-40. doi: 10.1364/oe.17.003331.
We use a Fabry-Perot cavity to optically filter the output of a Ti:sapphire frequency comb to integer multiples of the original 1 GHz mode spacing. This effectively increases the pulse repetition rate, which is useful for several applications. In the case of low-noise microwave signal generation, such filtering leads to improved linearity of the high-speed photodiodes that detect the mode-locked laser pulse train. The result is significantly improved signal-to-noise ratio at the 10 GHz harmonic with the potential for a shot-noise limited single sideband phase noise floor near -168 dBc/Hz.
我们使用法布里-珀罗腔对钛宝石频率梳的输出进行光学滤波，使其成为原始1吉赫兹模式间隔的整数倍。这有效地提高了脉冲重复率，这对多种应用很有用。在低噪声微波信号产生的情况下，这种滤波可提高检测锁模激光脉冲序列的高速光电二极管的线性度。结果是在10吉赫兹谐波处的信噪比显著提高，有可能实现接近-168分贝毫瓦/赫兹的散粒噪声限制单边带相位噪声本底。
