Engineers talk about stunning laser applications

Karolis Jurkus and Rimantas Budriūnas, R&D engineers and winners of the Laser Focus World Gold-level Innovators Award, admit that news of the accolade came as a surprise, but a pleasant one. Karolis and Rimantas work at LIGHT CONVERSION and have designed an ORPHEUS-MIR optical parametric amplifier, the intricacy of its name only excelled by that of its application.

With a smile on his face, Rimantas, a physics PhD, commented: ‘I knew that LIGHT CONVERSION’s products kept on winning various awards. On the other hand, it came as a bit of a surprise – and it was very exciting that this time, it was something Karolis and I had made.’

Karolis Jurkus, who has been working at the laser laboratory for more than seven years now, was being honest when he said: ‘I never thought we would win any kind of award for our devices this year. After all, it is not what we develop new products for.’

The engineers shared their insights. Neither Karolis nor Rimantas accept full credit for their success: ‘I think it would be right to say that I am the one who came up with the initial idea for this device and who managed to convince my colleagues and the clients at the right time, while Karolis brought the first working iteration of this solution into fruition. However, even after our efforts, many other colleagues worked on it until the device reached its current, award-winning form.’

Hardly a household item, but heaven for researchers

Karolis began his presentation by explaining: ‘To put it in simple terms, the optical parametric amplifier is a laser light source that can change the wavelength it radiates (or the color, if you will). This is its key feature and its advantage. It is a source capable of generating both ultraviolet, visible and infrared radiation with a broad range of applications.’

When they were developing the device, the researchers focused first and foremost on its application for the purposes of a single research methodology – the so-called sum-frequency generation spectroscopy. Rimantas went into greater detail: ‘It is a unique approach, one that stands out in the way that it provides information solely about the processes taking place on the surface of samples or at the interfaces of different materials. With our light sources, femtosecond lasers, this measurement can be done with the temporal resolution, making it possible to observe how the molecules of one surface bind with the molecules of another surface.’

Even though surface science is mostly a chemistry field, the interesting fact is how this branch with its exotic name can be used to address down-to-earth matters. For instance, why the skin of a snake will not wear away as the reptile traverses rough surfaces, despite its excellent traction with the surface.

Referring to this field of application, the researchers commented: ‘For instance, the first buyers of ORPHEUS-MIR, who placed the order for the device to be made in the first place, performed a lot of research relating to the exceptional abilities of different animals. What are the qualities of a frog’s tongue that make it so incredibly sticky? Can they be used to make new, better types of glue? The answer can be found through sum-frequency spectroscopy.’

orpheus-mir applications
R&D engineers Rimantas Budriūnas and Karolis Jurkus are the winners of the Laser Focus World Gold-level Innovators Award.
Nail Garejev photo.

Cancer treatment and the bombardment of mice brains

It is now obvious that even though the parametric amplifier is of little use around the house, it is an absolute must in the daily life of many scientists.

As previously mentioned, exposing the surface of a material to laser radiation can reveal its composition as well as the processes that are taking place within it – processes that are invisible to the naked eye. In this regard, Karolis shared a memory. ‘The radiation produced by the devices that we design is used to crack the composition of molecules, look for new ways to diagnose cancer, and observe the gyri of a mouse’s brain. By replacing part of a mouse’s skull with glass with a fiber attached, researchers use our lasers to bombard its brain and observe how the light activates the neurons. I remember one of our clients recently bragging about how he could irradiate a piece of a semiconductor with our laser in his lab, turning it into a piece of metal, and the other way around… It’s like alchemy.’

Designed by these two researchers, the parametric amplifier has its primary application in the field of material composition, its key unique characteristic being the high firing rate compared to other devices available on the market. To put it in simple terms, this makes daily life easier for researchers and saves precious time.

As Karolis said: ‘Picture, if you will, a scientist secluded in a lab, holding a sample of the test material under laser light, patiently waiting for seven days and nights, praying that the laser does not fail during that time, and hoping he will be able to collect enough data about the test material. With our device, the same amount of data can be collected within an hour.’

One year in development

Karolis pointed out that the idea for this unique device was prompted by fellow scientists: ‘We crossed paths with a group of researchers who were looking for an infrared radiation light source with unique features that would work at a rate that none of us had ever seen before, but one that they had been dreaming about for years.’ The researchers, who receive an impressive number of custom orders every year, saw this as a challenge and built a working device within one year.

The development process did not stop with the creation and delivery of the first devices to the clients. ‘Following installation at the client’s lab, our heads were full of ideas of how this device could be made better and its modus operandi simpler; as a result, when we got back, we spent a few months or more building a final, complete product,’ said Karolis, whose involvement in this field began at the National Cancer Institute.

The team maintained that their prediction had been that the final, fully developed product would spark interest. World-class lasers designed at LIGHT CONVERSION’s laboratories are shipped all over the world and delivered to the laboratories of the world’s top universities. The company is a leading global manufacturer of tunable wavelength femtosecond laser sources as well as diode-pumped solid-state femtosecond lasers.

Of course, not everything has been rosy. There were some problems working with light: unseen by the human eye, it is also ‘invisible’ to most of the devices designed to measure laser radiation, such as cameras, spectrometers, etc.

Rimantas, who plays with the dark rock band Gija in his free time, spoke about the hardships they had faced: ‘We had to both design the device as such and look for devices or methods that would help us realize whether the prototype was working the way we wanted it to.’

Karolis added: ‘All of a sudden, we came face to face with what was physically possible, and it made us reconsider the working principles of the device and look for alternative ways to achieve the specifications we had in mind. The biggest challenge was to harness physics and to make a complicated, clunky, yet working device smaller, simpler, and more reliable. Turning complicated things into ones that are simple is an art, but that is exactly why Lithuanian lasers receive so much love.’

Lithuania’s potential is huge

The researchers are excited about the recently fast-growing potential of Lithuanian lasers. Karolis lightheartedly suggested that lasers have become a national treasure in Lithuania and have earned an honorary place somewhere between cold beetroot soup and basketball. He added that many people who know nothing about lasers have heard of Lithuania’s success in this field.

‘As the market is growing at a crazy speed, there is a lot of potentials for Lithuanian companies to grow and expand as well. I think that the success story of Lithuanian lasers has yet to reach its apogee.’

Original article was published in www.15min.lt