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Bandwidth-independent linear method for detection of the carrier-envelope offset phase
Karoly Osvay1, Mihaly Görbe, Christian Grebing
1Department of Optics and Quantum Electronics, University of Szeged, Hungary. osvay@mbi-berlin.de
Optics Letters
|November 3, 2007
Summary
We developed a new linear method to measure the carrier-envelope offset (CEO) phase in femtosecond lasers. This technique uses interferometry and a ring resonator for precise measurements, even at low power levels.
Area of Science:
- Optics and Photonics
- Laser Physics
- Ultrafast Science
Background:
- Accurate measurement of the carrier-envelope offset (CEO) phase is crucial for controlling femtosecond laser output.
- Existing methods often rely on nonlinear optical processes, limiting their applicability to low-power or low-bandwidth oscillators.
Purpose of the Study:
- To propose and demonstrate a novel, linear optical procedure for measuring the CEO phase of femtosecond oscillators.
- To enable CEO phase characterization for a wider range of laser systems, including those with low bandwidth and power.
Main Methods:
- Utilized a Mach-Zehnder interferometer in conjunction with a ring resonator and a spectrograph.
- Employed spectrally and spatially resolved interferometry to detect fringe visibility.
- Exploited the modification of interference contrast between subsequent and identical pulses, dependent on the CEO phase.
Main Results:
- Demonstrated that fringe visibility uniquely depends on the CEO phase of the pulse train through numerical simulations and experimental validation.
- Confirmed the linear nature of the proposed technique, avoiding nonlinear optical conversions.
Conclusions:
- The developed linear procedure offers a robust and versatile method for measuring the CEO phase.
- This technique significantly expands the capability to characterize CEO frequencies in mode-locked oscillators, irrespective of their bandwidth or power levels.
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