CEP stabilization loop

Dazzler / Fringeezz combination for multi-kHz, single-shot CEP stabilization

The combination of the Dazzler or high repetition rate Dazzler single-shot and dispersion-free CEP control, with the multi-kHz single-shot CEP detection of the Fringeezz allows to build high bandwidth Carrier Envelope Phase stabilization loops.

The ultimate CEP control for Ti:Sa amplifiers, OPCPAs or other CEP-compatible systems, as well as for high-stability interferometers.

The Fringeezz measures the Carier Envelope Phase noise encoded in the interferogram produced by a f-to-2f setup. The plug & play connection with the Dazzler CEP control module allows multi-kHz retroaction on the CEP, without any alteration of the pulse compression.

Plug & play

Although the Fringeezz can be used with any high speed and high accuracy CEP actuator, its combination with the Dazzler CEP control module is effortless, providing almost instantaneaously dramatic improvement of the CEP stability.

Up to 5kHz retroaction bandwidth – Loop efficiency demonstrated on 100kHz systems.

Since the Fringeezz measures the CEP error for all laser shots at repetition rates up to 10kHz, The retroaction bandwidth can be as high as 5kHz, thus eliminating most of the frequency noise contributions. Indeed, the Power Spectral Density data of a closed loop system evidence a residual white noise structure: all distinctive drifts and noise contributions from mechanical or atmospheric origin have been eliminated.

Although the Fringeezz extract the CEP error value every 100µs, the application of the Dazzler/Fringeezz feedback loop is not limited to sub 10kHz systems.
With its ability to perform single pulse measurement at 100kHz, coupled with the filtering possibilities of the feedback process, sub 100mrad single-shot stabilization has already been demonstrated on our 100kHz OPCPA systems.

CPA or OPCPA Carrier Envelope Phase stabilization

The Dazzler / Fringeezz feedback loop has already demonstrated record CEP stability values on Fastlite high flux MIR OPCPA systems.

Below are open loop/closed loop and on/off PSD CEP data obtained on a 100kHz OPCPA system at 3µm.


Open loop
Closed loop
Interferometer stabilization

Polarization shaping experiments, or coherent pulse synthesis, require to separate and then recombine broadband optical pulses with an excellent phase stability.
The Dazzler / Fringeezz feedback loop is the ideal tool for this application.


Data below shows the result of a Mach-Zhender interferometer stabilization at 7kHz, resulting in a sub 25mrad rms phase noise (single-shot).

CEP versus time.
red: open loop, black: closed loop: 25mrad rms single shot
Power Spectral Density
red: open loop, black: closed loop