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Ultrafast Laser Physics and Precision Metrology Group

Jobs / Positions

Laser Development: from ultra-intense to ultra-stable

Frequency combs
TW-peak power parametric ultrafast amplification

We have developed TW-class optical parametric amplifier systems over the years for different purposes, such as high-harmonic generation of X-rays and for phase-coherent amplification of ultrafast pulses for frequency comb metrology. The shortest pulses we have produced at few-TW level are 7.6 fs (up to 3 TW at a 30 Hz repetition rate). Currently the development focuses on two aspects. One is two-pulse amplification for Ramsey-frequency comb spectroscopy. The other is production of 10 fs, TW-level pulses at 300 Hz repetition rate for water-window (2-4 nm) X-ray generation. We recently finished the pump laser for this system, and published an article in Optics Letters about it:

D.W.E. Noom, S. Witte, J. Morgenweg, R. Altmann, K.S.E. Eikema
High-energy, high repetition rate picosecond pulses from a QCW-diode pumped Nd:YAG system
Optics Letters 38, 3021-3023 (2013)

Other papers:

S. Witte, K.S.E. Eikema, "Ultrafast Optical Parametric Chirped-Pulse Amplification"
Invited, IEEE Journal of Selected Topics in Quantum Electronics 18, 296-307 (2012)

D.Z. Kandula, A. Renault, Ch. Gohle, A.L. Wolf, S. Witte, W. Hogervorst, W. Ubachs, K.S.E. Eikema,  "Ultrafast double-pulse parametric amplification for precision Ramsey metrology"
Opt. Express 16, 7071-7082 (2008)

A. Renault, D.Z. Kandula, S. Witte, A.L. Wolf, R. Th. Zinkstok, W. Hogervorst, K.S.E. Eikema, "Phase stability of teraWatt-class ultrabroadband parametric amplification"
Opt. Lett. 32, 2363-2365 (2007)

S. Witte,R. Th. Zinkstok, W. Hogervorst, K.S.E. Eikema,
"Numerical simulations for performance optimization of a few-cycle terawatt NOPCPA system"
Appl. Phys. B. 87, 677-684 (2007)

S. Witte, R. Th. Zinkstok, A.L. Wolf, W. Hogervorst, W. Ubachs, K.S.E. Eikema, "A source of 2 terawatt, 2.7 cycle laser pulses based on noncollinear optical parametric chirped amplification"
Opt. Express 14, 8168-8177 (2006)

Ultra-stable Lasers

We are developing ultra-stable lasers for applications such as frequency and time-transfer over fiber networks at wavelengths near 1550 nm based on diode lasers.
Recently we acquired a <1Hz bandwidth laser system operating at 1542 nm from Menlo Systems (see photo). The system is financed by a FOM Program "Broken Mirrors and Drifting Constants", and together with a Cs III atomic clock from Symmetricom it will provide a reference system to improve many experiments that require high accuracy.
Currently a temperature stabilized 'quiet room' is constructed where the sub-Hz laser will be installed, together with the Cs atomic clock, and a frequency comb.

precision spectroscopy

coh control
Fiber-link LaserLaB - KVI Groningen

We are working on a fiber link between the LaserLaB and the KVI in Groningen. The project is sponsored by Surfnet, and coordinated by dr. J. Koelemeij. Since spring 2012 we have a bi-directional link in operation on a commercial channel. The idea is to transfer frequency and time signals over the link with a better precision than GPS currently allows. In the future we hope to have access to a 'dark-fiber' for fully length-compensated operation of the link for the highest performance. We are also actively pursuing future participation in a European time and frequency dissemination network.

We gratefully acknowledge financial support from:
NWO FOM Laser Europe surfnet VU fp 7 framework

Questions? Contact: k.s.e.eikema@vu.nl