Physicists of University of Jena Triple Pulse Energy of POLARIS Laser
POLARIS is the world's most powerful fully diode-pumped laser system and with it, the University of Jena possesses a petawatt-class laser, which produces the presently highest-performing laser pulses.
A team of physicists under the leadership of Prof. Dr Malte Kaluza at the Institute of Optics and Quantum Electronics has now succeeded to once again improve POLARIS' performance significantly. For the first time, the laser has produced pulses delivering an energy of more than 50 Joule, which is more than three times as high as before.
50 Joule is the amount of energy needed to lift an object weighing 500 g approximately 10 m off the ground; to raise the temperature of a glass of water by only one degree, however, 17 times as much energy would be required. For a high-performance laser system like POLARIS, 50 Joule therefore seems rather meagre.
„But our laser system delivers this amount of energy in a very short time interval,“ explains Prof. Kaluza. The laser pulses have a duration of 120 femtoseconds only. In this unimaginably brief moment – a femtosecond is one thousand-million-millionth of a second –, the laser reaches a peak power of several hundred terawatts (TW). This is many times higher than all the electrical power produced worldwide.
This increase in the laser system’s performance is the result of several months of development. „The basic architecture and set-up of the laser have not changed,“ underlines Prof. Kaluza, „but we succeeded in changing and improving many small details decisively.“
The recent results and achievements were also made possible through a long-term cooperation with the local optics industry – in particular with the Jenoptik AG, with Lastronics GmbH, with Hellma Materials GmbH, and with Layertec GmbH –, who have provided some of the core components of the laser system. For example, the last and largest power amplifier of POLARIS now uses ytterbium-doped calcium fluoride crystals.
And also the optical coating of the materials put under enormous stress by the laser radiation has been further optimized. „All these small changes together now allow us to reach a considerably higher laser energy than before,“ explains Kaluza. But the laser physicist also suggests that the 54.16 Joule reached now are far from being the finish line.
As the next stage in the development, Kaluza, who also is the holder of the chair of experimental physics and relativistic laser physics, now plans to shorten the duration of pulses in the POLARIS system even further, the goal being to reduce the duration to no more than 100 femtoseconds. The steady reduction of the duration is, however, not a goal in itself.
„We are not looking to always set new records,“ explains Kaluza. On the contrary, the objective is to make POLARIS available for specific uses. First and foremost, the laser is meant to be used as a tool for particle acceleration. „We have already conducted some first experiments in this field with lower pulse energy and longer laser pulses. Now we are excited to see how the particle energy will scale with the much higher laser energy and concurring shorter pulse duration.“
Intense and highly energetic ion radiation can, for example, be used in tumour treatment. So far, the generation of these highly energetic particles required tremendous technical efforts in very large particle accelerators.
„With the amount of energy we are now able to generate, we can offer laser systems like POLARIS for particle irradiation, which are comparatively ‘easy to handle’ and manageable. We are now curious to see to what particle energy we can now make it with the new laser pulses,“ says Prof. Kaluza.
Information on POLARIS:
The name POLARIS stands for „Petawatt Optical Laser Amplifier for Radiation Intensive Experiments.“ The project in the framework of which POLARIS was developed was launched at the University of Jena in 1999. The laser has been continuously developed ever since and currently is the world’s only fully diode-pumped laser system generating pulses with a peak power of more than 200 TW and can thus be used for high-intensity experiments. More information at: https://www.hi-jena.de/en/helmholtz_institute_jena/experimental_facilities/local...
Prof. Dr Malte Christoph Kaluza
Institute of Optics and Quantum Electronics of the University of Jena
Max-Wien-Platz 1, 07743 Jena, Germany
Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
Phone: +49 (0) 3641 / 947280
Dr. Ute Schönfelder | idw - Informationsdienst Wissenschaft
Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University
Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences