The two oscillator circuits beneath are well suited for using crystal oscillators in series or parallel method: Superior-repetition-rate and large-electrical power picosecond regenerative amplifier according to an individual bulk Nd:GdVO4 crystal 中原子或分子的排列具有三维空间的周期性，隔一定的距离重复出现，这种周期性规律是 A superior power passively mode-locked picosecond oscillator ... https://livebookmarking.com/story18932077/the-2-minute-rule-for-bulk-crystal-oscillator