Laser 4: 10 PW, 2 kJ

Eli Beamlines L4 Laser

Laser 4: 10 PW, 2 kJ

Řetězec L4 je určen ke generování extrémně vysokého a dosud nevídaného špičkového výkonu 10 PW (petawattů) při délce trvání pulzu asi 130 fs. Nekomprimovaná energie může dosáhnout hodnoty téměř 2 kJ s frekvencí výstřelů za min, což představuje významný pokrok v oblasti laserů v kJ třídě. Architektura je založena na přímé kompresi širokopásmového svazku zesíleného kombinací různých desek neodymového skla. Laser je vyvíjen konsorciem National Energetics (USA) a EKSPLA (Litva). [Podrobné informace jsou prozatím k dispozici v anglickém jazyce.]

The L4 system architecture

The L4 laser system can operate in two main modes:

  • All the energy can be used to generate a power of 10 PW in a single beam. By-pass of the compressor is possible in order to use the chirped nanosecond (ns) beam directly.
  • The main amplifier can deliver almost 2 kJ in a narrowband ns beam with variable temporal shaping seeded by a separate front end. At the same time, the broadband front end can seed the first main amplifier and thus provide a 200 J-class PW pulse.

The L4 laser chain is composed of a broadband ultrafast oscillator, picosecond OPCPA preamplifier, nanosecond OPCPA stages, and two main amplifier stages based on Nd:glass-gain media pumped by flashlamps. The resulting nanosecond pulses are compressed in a dielectric grating compressor.

L4 beam line design parameters (main beam)

Output pulse energy (main beam compressed)

>1,800 J in single aperture

Pulse duration (CPA regime)

<150 fs FWHM (adjustable to 100 ps)

Pulse duration (non-CPA regime)

0.5–5 ns (temporal shaping adjustable in 150 ps steps)

Repetition rate

1 shot per minute

Peak power

10 PW

Pump laser technology

flashlamp-pumped Nd:glass amplifiers

Output laser pulse energy RMS stability 

better than 10% rms

Output laser beam RMS pointing stability

<10 µrad

Laser control system

Labview and EPICS

Output pulse external synchronization relative to the facility clock

<20 ps to RF clock with any delay relative to facility clock

Beam format 

rectangular superGaussian

Beam size of compressed beam

<550x550 mm

Delivery of the system

The delivery of the L4 laser system was contracted with the United States-Lithuanian consortium of National Energetics and Ekspla in September 2014.

The main subcontractors are Schott and Lawrence Livermore National Laboratory.

ELI-Beamlines staff is in charge of delivering for the following subsystems:

  • Full diagnostics of the compressed 10 PW beam
  • Design of the vacuum vessel for the 10 PW compressor
  • Design and delivery of optomechanics for the 10 PW compressor
  • Laser timing platform
  • Contribution to the development of long pulse OPCPA amplifiers.

Daniel Kramer daniel.kramer@eli-beams.eu

Související stránky

Výzkum / Laserové technologie / Petawatt Lasers

ELI Beamlines' laser team is developing and co-developing, in partnership with major laser technology suppliers of the project, a number of essential systems for Petawatt (PW) and 10-PW lasers.