CERO 技术

针对差频光梳(DFC)的"零载波包络偏移频率 fCEO" 技术

  • 利用铒搀杂光纤振荡器及非线性光纤产生宽带超连续谱
  • 非线性晶体中超连续谱高频低频光谱间差频生成
  • 两部分光谱均具有相同 fCEO
  • 所得光梳载波包络相位稳定至0
  • TOPTICA 专利(DE102004022037)

Difference Frequency Combs

 

TOPTICAs frequency comb DFC shows quadratic scaling of the phase noise with frequency. This textbook like behavior has been shown to a remarkable degree. The DFC behaves like an elastic tape with a true fixpoint at zero. An ideal system to be combined with an optical reference. Characterization of a DFG comb showing quadratic scaling of the phase noise with frequency, T. Puppe et al., Optics Letters Vol. 41, Issue 8 (2016)

“The DFG comb possesses a vanishing carrier envelope offset frequency that permits the construction of a simple and thus potentially more stable optical clockwork.Zimmermann, Gohle, Holzwarth, Udem and Hänsch, Opt. Lett., 29, 310 (2004)

“This all passive approach provides extremely reliable and rigid locking of fCEO on both short and long time scales”, Krauss, Fehrenbacher, Brida, Riek, Sell, Huber, and Leitenstorfer, Opt. Lett., 36, 540 (2011)

“… in this nonlinear process the phases of the two pulses add up with different signs, leading to CEP cancellation and resulting in passive, all-optical phase stabilization.”Manzoni, Cerullo, and De Silvestri, Opt. Lett., 29, 2668 (2004)

“The unique feature … is that fCEO of the DF is zero without any servo-loop feedback system; i.e., the waveform is self-stabilized in the resultant pulse train.” “The generated phase-stable pulses may - after preamplification - be suitable for seeding high-gain Ti:sapphire amplifiers and (or) the oscillator itself.”Fuji, Apolonski and Krausz, Opt. Lett., 29, 632 (2004)

CERO 技术原理简介

无偏移差频光梳(DFC)的操作原理依赖于由低噪声铒搀杂光纤锁模振荡器产生的宽带超连续谱及经由该连续谱高频及低频部分在非线性晶体中的光学差频产生(DFG)。最重要的特性是优化的稳定性以及更加简单可靠,全无源器件的频率偏移稳定机制。由于原始光谱高低频部分具有相同的共模抑制,该光梳不会受到偏移相位以及偏移频率的扰动。另外,DFC的载波包络偏移频率 fCEO被设定为零。

这种无源,全光学的fCEO稳定机制比起传统的f to 2f 干涉仪有很明显的优势。频率计量领域的几个主要研究人员均已在文章中指出这一点(Krauss et al., Opt. Lett, 36, 540 (2011))。无源稳定机制最大的优点在于其不受电子噪声的干扰。另外,系统无需进行载波包络偏移校准或复杂的偏移补偿。系统无需载波包络偏移锁定电子器件,从而极大地减少了电子器件封装的复杂性。该系统中唯一可调的参数是DFC的重复率。它可以很容易地稳定至GPS同步射频参考。用户可选择DFC输出的几个特定波长以满足自己的实验需求。

 

CERO 技术原理

差频光梳(DFC)非常适用于原子光学应用中的频率参考,同时也能够满足频率计量以及光钟应用中频率稳定的精密要求。该方法尤其适用于需要窄线宽激光等光学参考的情况。在以这样光学参考做参照稳定的情况下,光梳频率可通过差频产生方法紧紧锁定至0Hz,或者通过光学参考的方式锁定至光频率参考。在这里,CERO技术相比于传统的f-to-2f干涉方法有明显优势,因为后者的载波包络偏移高频噪声无法被消除。

The CERO-products