It has taken almost 20 years. But now Korean researchers have reached the world’s highest laser intensity.
Ultra-high intensity laser is an important research tool in several fields. A research group in Michigan in 2004 succeeded in reaching a laser intensity of 1022 watts per square centimeter. Since then, many researchers have strived to reach the next step, 1023 watts per square centimeter.
To reach such a high, you need a laser with extremely high power and an opportunity to concentrate the laser beam to a small point.
Continuous lasers, which emit a constant beam of light, can not achieve as high an effect as pulsed laser systems, which emit very short light pulses. Several such pulsed laser systems, with a power of 10 petawatt and higher, have been built or are planned in different parts of the world.
“All sunlight that reaches the earth at a point of ten micrometers”
A research team at the Korean Institute for Basic Science has been using a 4 petawatt laser system since 2016. In April this year, they finally managed to break the record. Then they reached just over 1023 watts per square centimeter.
To succeed, researchers have amplified, reflected and concentrated the beam in several steps, including the use of deformable mirrors.
Research leader Chang Hee Nam likens the intensity of the laser beam to collecting all sunlight that reaches the earth at a point as large as a grain of dust.
– The laser intensity of 1023 watts per square centimeter is comparable to the light intensity you would get if you concentrate all sunlight that reaches the earth at a point of ten micrometers, he writes in an email to the media company Vice.
Recreate cosmic high energy radiation
According to scientists, the feat opens the door for basic theoretical questions in the universe to be explored through experiments. With high-intensity laser pulses, cosmic high-energy radiation can be recreated in the lab so that scientists can investigate phenomena that are believed to have arisen early in the universe and from supernova explosions.
– With the highest laser intensity ever achieved, we can tackle new challenging areas in experimental research, says Chang Hee Nam in a press release.
But researchers also believe that this type of laser, and future versions with even higher intensity, could provide more down-to-earth benefits in the form of cheaper cancer treatment.
“Exciting news for cancer patients”
Today there is a new type of cancer treatment called proton radiation. It involves protons being pushed against the patient’s tumors at high speed using an accelerator. The purpose is to damage the DNA of the tumor cells so that they cannot continue to divide.
The proton beam can be controlled very precisely, which reduces the risk of damaging healthy tissue next to the tumor cells. However, the use of accelerators means that the method requires large and expensive radiation protection.
With laser beams, the Korean research leader believes that the protons could be aimed in the right direction in a cheaper way. Thus, the treatment could be available to more patients.
“The development of cheaper proton machines in oncology will be exciting news for cancer patients,” Chang Hee Nam told Vice.
The research results have recently been published in the scientific journal Optics.