Innovations Beyond the Visible: Laser Nanotechnology Opens New Dimensions New application area of the HiLASE Centre | LNT

At HiLASE Centre we are eager to push the boundaries of laser technologies beyond their current limits, search for new applications and contribute to the prosperity of the Czech and European economy, daily lives of people and sustainable future. We strive to inspire the next generation of laser scientists, engineers and entrepreneurs.

In line with our vision, we have strategically chosen the field of Laser nanotechnology (LNT) as one of our newly defined strategic areas.

Laser nanotechnology is a rapidly evolving field at the intersection of laser science and nanoscale engineering, and holds immense promise for revolutionizing various industries and transforming our technological landscape.

The main guarantor of this area is Prof. Nadezhda Bulgakova, Dr.Sc.; Head of the Scientific Laser Applications Department. We asked Nadya for an interview in which she will introduce LNT.

What is laser nanotechnology and how it works?
Nanotechnology is the field of science and engineering that deals with designing, fabricating, and using structures in real applications, for example, devices, by manipulating atoms and molecules at the nanoscale from several to hundreds of nanometers. Nanotechnological investigations are currently a very rapidly developing field of the natural sciences. Often nanomaterials have very different properties compared to the same materials made at larger sizes and this offers unprecedented new opportunities in nowadays applications. Nanotechnology developments have the great potential to significantly impact society, which is already evident in some industrial and biomedical sectors such as data processing, communications, and increased computing functionality. It is already used in food and energy technologies and in some medical products and cosmetics. Important is that nanomaterials may offer new opportunities for the reduction of environmental pollution due to their extraordinary catalytic and antibacterial properties.

Laser nanotechnology is a branch of nanotechnology, but it offers widening options for manipulation by nanoobjects. I can mention only a few of them, high selectivity as was demonstrated by us in laser annealing of germanium nanolayers in germanium/silicon, high localization of nanostructured objects or their structural transformations, high purity of the synthesized nanomaterials, and applicability to any material. All these options are not achievable or achievable in multistep expensive methods in other nanotechnological applications such as chemical or mechanical production of nanomaterials.

Thus, you can work with a laser beam as with a tweezer or nanoscale scalpel for manipulations with nanoobjects while for nanomaterial synthesis you can destroy any materials to atoms or molecules to assemble a material with novel properties (that is usually called ‘bottom-up’ approach). 

What are the applications of laser nanotechnology?
The applications of laser nanotechnology are wide, and they are rapidly growing. Important is that lasers offer green ways for nanomaterial synthesis and manipulations that avoid toxic chemistry. Laser synthesized nanoparticles are suitable for medicine, in particular for cancer diagnostics and treatment and also for other diseases such as cardiovascular. Nanomaterials prepared by laser synthesis can be applied for enhancing the resolution of microscopy, for sensing, for example for identification of toxic components, drugs, or viruses in blood, and for environmental purposes such as sensing and destroying air or water pollutants.

Can you provide us with a brief overview of topics like pulsed laser deposition of 2D materials, laser-annealing synthesis of 2D materials from liquid precursors, laser direct printing of 2D materials, 2D material functionalization, non-invasive laser theranostics, laser surgery with tailored laser beams, pulsed laser fabrication of biocompatible interfaces, please?
Nowadays, two-dimensional materials represent a very wide class of materials. They are sheets with a thickness of only one atom. These sheets can be combined in stacks and any combination provides new properties which were not found before in other materials, such as extremely high conductivity, combinations of plasmonic and magnetic properties, also enhanced response to specific laser wavelengths. They may serve as building blocks for micro and nanoelectronics to be used in mobile phones, detectors, and novel types of high-performance computers. Laser light is used to synthesize such materials via pulsed laser deposition when you destroy a big piece of material into atoms and these atoms are deposited to a substrate thus composing sheets of 2D materials. We have several vacuum chambers where we investigate such kind of synthesis with the aim to find optimal conditions for the most functional 2D materials for various applications. Another way can be in laser deposition of 2D materials from liquid precursors, usually salts of metals; this method is still at the beginning of development in our laboratory but as practice shows it is very perspective. One of the problems which is under solution in our laboratory is the precise positioning of 2D material sheets for printing micro-nano electronic devices. Dr. Goodfriend and Prof. Bulgakov have invented an apparatus for these purposes which is now protected by patent. Such manipulation by one atom thick sheets is in high demand in industries working toward novel computing, communications, and sensing applications.

Another substantial direction of our research led by Dr. Ryabchikov is the synthesis of new hybrid nanomaterials composed of metals and semiconductors which would combine plasmonic and magnetic properties while being low-toxic for the human body. Such nanoparticles are now synthesized in our laboratory by laser ablation in water and they may represent new ways for non-invasive diagnostics and therapy, so-called theranostics, of cancer and cardiovascular diseases with suppressed side effects although much more effort must be done for introducing such methods to hospitals. But I believe that one day such gentle non-invasive and very efficient treatment will become true.

There are several not less important applications of nanotechnologies where we have already achieved substantial progress, thanks to the HiLASE lasers with unique parameters of light generation. I can mention selective and highly localized laser annealing of semiconductor nanolayers and nanostructural materials and nanostructuring of surfaces of different materials where we also obtained a European patent.

Which topic will we, as the HiLASE Centre, focus on the most?
Thus, based on what was already mentioned, we will mostly focus on 2D material and nanoparticle laser synthesis with the development of real applications such as the fabrication of circuits, sensors, and detectors based on the synthesized materials. Another direction which is of utmost interest to us is laser theranostics and applications of the developed laser techniques for environmental problems to make our planet cleaner.

Try to outline the benefit to society, the environment, and the impact on science and from the other perspective the impact to HiLASE itself.
Each of our developments or discovery in the listed directions of research can be a milestone not only for science but for society. As mentioned, our research efforts can lead to new advanced technologies in computing, communications, sensing, and medical treatment, that are devoted to making human life better, safer, and healthier. This is our dream to contribute to a better future for humankind. The HiLASE Centre combines a wide range of capabilities starting from the development of lasers with record power and wide radiation parameters, a strong engineering team and large scientific potential. Laser nanotechnology can become one of the pillars of HiLASE sustainability and visibility on the world level.

What are the current limitations of laser nanotechnology and how can they be overcome?
Laser nanotechnology is a relatively young field, as is nanotechnology itself. A huge number of different materials and a wide range of laser sources offer the whole horizon of possibilities for tailoring new materials with novel properties with finally advancing them to new applications some of which could be imaging now as science fiction. Researchers working in nanotechnologies are like couturiers. It is extremely important to identify the most promising materials, and tools for their manipulations and tailoring, to foresee possible final applications. For this, it is important to have a wide and deep education, combining knowledge from different fields. Thus, the education of the young generation of scientists who could work successfully in nanotechnology, and particularly in laser nanotechnology is the way to advance this field.

How can laser nanotechnology be applied in medicine to improve diagnostics and treatment?
OK, a simple explanation can be as follows. Nanoparticles of specific materials, mostly metals, are objects highly absorbing laser light at certain wavelengths. Being injected into the body and irradiated by a gentle laser light which is not burning human tissues, they are heated very locally, each at the nanoscale, thus destroying tissues at nanosized volume. In such a way, cancer cells or thrombosis can be destroyed without bleeding which is non-invasive way. The main direction here is a synthesis of nanomaterials which are non-toxic and would combine strong plasmonic, magnetic, and optical properties. One of the variants of such hybrid metal/semiconductor nanomaterial was recently synthesized in our department. This nanomaterial can be also used for diagnostics,  for example by improving the resolution of tissue image or for sensing of blood composition, and detecting harmful inclusions in blood or lymph.

What are the potential environmental and safety implications of using laser nanotechnology in industrial applications, and how can they be mitigated?
Dealing with nanotechnology must be careful work. Nanostructured materials, especially nanoparticles can be dangerous. Many of them have extremely high chemical activity, it is why they are used as efficient catalytic agents. But this chemical activity can be toxic for living organisms. It is why we are searching for low-toxic nanomaterials. However, laser nanotechnology as we are using has advantages as compared to other methods, e.g., chemical, or mechanical nanomaterial production. We are using laser deposition in a vacuum and synthesis of nanoparticles in liquids (getting colloids of nanoparticles) that allow us to avoid spreading them in the atmosphere. However, we take care to prevent any occasional spreading of nanoparticles in the environment.

How can laser-based spectroscopy and imaging techniques be employed to characterize and analyse nanostructures, and what are the key challenges in achieving accurate measurements at the nanoscale?
At HiLASE we have wide possibilities of diagnostics for nanoobjects. This includes AFM, SEM, time-of-flight mass spectrometry with very high resolution up to a single atom, and Dynamic Light Scattering (DLS) instrument for nanoparticle analysis. Nowadays, there are wide possibilities for accurate measurements at the nanoscale. Yes, we would like to have other devices such as XPS (X-ray photoelectron spectroscopy) which is a very expensive device and at present is not affordable for us. But we have an extensive collaboration both here in the Czech Republic and abroad where we are offered additional diagnostics.  

What are the latest advancements in laser nanotechnology and how are they revolutionizing various industries?
Among the most exciting advancements of laser nanotechnology is large scale production of nanoparticle colloids achieved in the group of Prof. Barcikowski at the University of Duisburg-Essen, Germany. Before it was considered that laser generation of nanoparticles is a slow process and cannot be moved to an industrial level. I should mention that we are happy to collaborate with this group. Thus, laser produced nanoparticles can now be purchased at a reasonable price and, as I already mentioned, of very high chemical purity.

Another breakthrough can be seen in microfluidic sensing devices usually called lab on a chip with plasmonic nanostructures inside the microchannel, all prepared with laser and sensing also is performed using laser light. These devices work fast and show extremely high sensitivity to foreign inclusions in liquids, including blood, lymph, and other human fluids. This is a big step in biomedicine. One of the leaders in this field is Prof. Sugioka from RIKEN, and we are pleased to collaborate with him. For us, this kind of collaboration is a recognition of our successful efforts in this field.

I can also mention Laser fluorescence microscopy which has recently revolutionized imaging of bacteria, viruses, and even DNA.

What are the future prospects and potential advancements?
Among potential advances, I can repeat applications of laser nanotechnology in biomedicine as already discussed before and sensing devices, including the environmental sector. These are the most important sectors which can have a high impact on society on one hand but on the other hand, the achievements in these directions are feasible. However, the future can bring us new discoveries which are predicted now and not expected. Hopefully, they will also serve for a better future for humankind.

How the LNT fits into our vision and mission?
Laser nanotechnology at the HiLASE Centre is already under extensive development. We have got international recognition due to our achievements, such as selective laser annealing of nanoobjects, and in particular due to specific properties of the lasers developed at the HiLASE Centre, as well as unique non-toxic multifunctional nanoparticles for bio-applications. Pioneering is the development of the device for precise printing of nanoobjects by blister-based transfer technique which is already demanded by several groups from abroad. Thus, LNT is an integral part of the HiLASE activity now and for the future.

What are the possibilities of cooperation with the HiLASE Centre and what we can offer to potential partners interested in cooperation within the Laser nanotechnology area?
We have extensive collaboration with the groups over the globe and our achievements in LNT attract new proposals for collaboration in surface nanostructuring, nanoparticle and 2D material synthesis, laser precise printing, and even diagnostic of nanomaterials, thanks to unique time-of-flight mass-spectrometer. Besides nanomaterial printing device and high-resolution mass-spectrometry, we are happy to have a broad range of lasers with different wavelengths, pulse durations, with high power which we can offer to our potential partners. Another strength is in theoretical capabilities to perform numerical simulations on different scales of laser excitation from microscales toward atomic ones taking into account quantum effects. Thus, I look to the future of laser nanotechnology at the HiLASE Centre with optimism.

Laser nanotechnology represents a gateway to new dimensions of scientific discovery, technological advancement, and medical breakthroughs. By pushing the boundaries of light manipulation at the nanoscale, it enables us to unlock previously untapped potential, revolutionizing industries and improving lives in ways we could have only imagined.

This interview with Prof. Nadezhda Bulgakova, LNT area guarantor, was conducted by Marie Thunová, Head of Marketing & PR.