FEL2011 - List of Authors (Wilcox, R.B.)

Paper	Title	Page
THPB01	Optical Comb and Interferometer Development for Laser Synchronization in Femtosecond FELs	561
	R.B. Wilcox, J.M. Byrd LBNL, Berkeley, California, USA R. Holzwarth Menlo Systems GmbH, Martinsried, Germany
	Funding: This work supported by the U.S. Department of Energy under contract DE-AC02-05CH11231 We describe a method of synchronizing lasers in FELs to potential sub-femtosecond precision using interferometry and optical clock techniques, and show supporting experimental results. This precision is needed for pump/probe experiments in ultrafast FELs. The proposed system consists of carrier/offset phase stabilized, pulsed lasers synchronized via a single optical frequency delivered over fiber, analogous to RF oscillators synchronized with a reference frequency, but at 200 to 400THz. Our tests of modelocked lasers, interferometers and stabilized CW lasers show that subsystems can perform to the required precision. We have synchronized fiber lasers to less than 10fs jitter using two different frequency comb line locking schemes, and demonstrated interferometers in a working FEL with less than 100as jitter over 150m fiber. Based on these tests and published work by others, we calculate the performance of an optimized, integrated timing system to be less than 1fs in the short term. Long term stability is maintained by feedback from X-ray/optical cross-correlation at the experiment.

Paper

Title

Page

Optical Comb and Interferometer Development for Laser Synchronization in Femtosecond FELs

561

R.B. Wilcox, J.M. Byrd
LBNL, Berkeley, California, USA
R. Holzwarth
Menlo Systems GmbH, Martinsried, Germany

Funding: This work supported by the U.S. Department of Energy under contract DE-AC02-05CH11231
We describe a method of synchronizing lasers in FELs to potential sub-femtosecond precision using interferometry and optical clock techniques, and show supporting experimental results. This precision is needed for pump/probe experiments in ultrafast FELs. The proposed system consists of carrier/offset phase stabilized, pulsed lasers synchronized via a single optical frequency delivered over fiber, analogous to RF oscillators synchronized with a reference frequency, but at 200 to 400THz. Our tests of modelocked lasers, interferometers and stabilized CW lasers show that subsystems can perform to the required precision. We have synchronized fiber lasers to less than 10fs jitter using two different frequency comb line locking schemes, and demonstrated interferometers in a working FEL with less than 100as jitter over 150m fiber. Based on these tests and published work by others, we calculate the performance of an optimized, integrated timing system to be less than 1fs in the short term. Long term stability is maintained by feedback from X-ray/optical cross-correlation at the experiment.