FEL2013 - List of Authors (Metzger, T.)

Paper	Title	Page
WEPSO73	High Average Power Seed Laser Design for High Reprate FELs	697
	R.B. Wilcox, G. Marcus, G. Penn LBNL, Berkeley, California, USA T. Metzger, M. Schultze TRUMPF Scientific Lasers GmbH + Co. KG, Munchen-Unterfoehring, Germany
	Funding: US Department of Energy, under Contract Numbers DE-AC02-0SCH11231. In the proposed Next Generation Light Source (NGLS), FEL designs use lasers to seed the FEL in an HGHG scheme or bunch the electron beam in an E-SASE scheme. The FELs would run at 100kHz to 1MHz, requiring high average power lasers. For the seeded FEL, laser modulation is applied at 200-240nm, with 250-700MW peak power depending on pulse length, which can vary from 100-10fs. The laser consists of a broadband oscillator and amplitude/phase shaper seeding an optical parametric amplifier (OPA). After recompression, the ~800nm pulse is converted to the fourth harmonic. Losses could be high enough to require 250W at 100kHz, making the OPA ~100x more powerful than existing femtosecond OPAs. In the E-SASE scheme, a single cycle of 5 micron light bunches the beam, which then radiates a short X-ray burst. This requires 100% fractional bandwidth, and precise phase control of the e-field within the pulse, as well as broad band compensation of dispersion throughout the laser path. Bandwidth can be increased by splitting the amplified spectrum into segments and coherently recombining. We present design concepts that are expected to meet requirements, and identify R&D needs.

Paper

Title

Page

High Average Power Seed Laser Design for High Reprate FELs

697

R.B. Wilcox, G. Marcus, G. Penn
LBNL, Berkeley, California, USA
T. Metzger, M. Schultze
TRUMPF Scientific Lasers GmbH + Co. KG, Munchen-Unterfoehring, Germany

Funding: US Department of Energy, under Contract Numbers DE-AC02-0SCH11231.
In the proposed Next Generation Light Source (NGLS), FEL designs use lasers to seed the FEL in an HGHG scheme or bunch the electron beam in an E-SASE scheme. The FELs would run at 100kHz to 1MHz, requiring high average power lasers. For the seeded FEL, laser modulation is applied at 200-240nm, with 250-700MW peak power depending on pulse length, which can vary from 100-10fs. The laser consists of a broadband oscillator and amplitude/phase shaper seeding an optical parametric amplifier (OPA). After recompression, the ~800nm pulse is converted to the fourth harmonic. Losses could be high enough to require 250W at 100kHz, making the OPA ~100x more powerful than existing femtosecond OPAs. In the E-SASE scheme, a single cycle of 5 micron light bunches the beam, which then radiates a short X-ray burst. This requires 100% fractional bandwidth, and precise phase control of the e-field within the pulse, as well as broad band compensation of dispersion throughout the laser path. Bandwidth can be increased by splitting the amplified spectrum into segments and coherently recombining. We present design concepts that are expected to meet requirements, and identify R&D needs.