Femtonics - Healing and Producing with Ultra-short Pulses

Who wouldn't prefer a totally painless treatment of dental caries? Femtonics makes it possible. Heat and vibrations cause pain during drilling. Both can be avoided with femtosecond lasers. However, this is just one of many applications of femtonics. The femtosecond laser enables materials processing with nanometre precision. With Diesel engines, and now also with Otto engines, femtosecond lasers can contribute to increasing the performance of the engine while reducing consumption and the burden on the environment. The interviewed expert explains how.

Femtonics deals with processes in the range of femtoseconds, i.e. of a trillionths of a second. A comparison can help to understand the order of magnitude: While light travels around the Earth about seven times in one second, it travels the hundredth part of a hair's breadth in one femtosecond.

The applications for laser pulses of such short duration vary greatly:  Such extremely short pulses can ensure that materials and, in particular, organic materials can be analysed and processed in a non-invasive way. Femtonics opens new fields of work for materials processing. So far, we were knocking on closed doors when it came to observe, understand and influence ultra-brief processes. Femtonic lasers now provide the opportunity to observe, influence and use - in a targeted way and for the benefit of man - processes in nature taking place in the femtosecond range, such as the oscillations of a molecule.

Femtosecond processes can only be created artificially by a laser. A femtosecond laser generates extremely short flashes of light. Materials can be processed with these femtosecond pulses - as with a conventional laser. The fact that the pulses are as short as the elementary processes in the material leads to important consequences:

• There is no zone influenced by heat around the processed area.
• There are no tensions and cracks around this area.
• There are no residues.

Femtonics can be used in many ways

Femtosecond laser in a laboratory (source: Würzburg University)

The characteristics of femtosecond lasers turn them into ultra-precise and low-damage tools which contribute decisively to meeting the challenges in different areas, such as mobility, production, health and environmental protection. The femtosecond technology is therefore a key technology. It influences micro and nano materials processing, information and communication technologies, measuring technology as well as the life sciences and medicine - all at the same time. Injection nozzles of the next generation for diesel engines, for example, which again reduce fuel consumption dramatically can only be drilled with femtosecond lasers.

• Cylinder walls of engines will be given a microstructure surface in future by means of femtosecond lasers, so that engines perform better while producing less emissions.
  Laser-structured cylinder slide way (source: Gehring)

All in all, fuel savings up to 20 percent are possible and enable a lower impact on the environment in spite of increasing private transport. The market potential of this application of femtonics alone is expected to be about 100 million Euro each year.

• Brain surgeries can in future be performed without causing damage to the surrounding tissue by means of femtonics. This means hope for patients with brain tumours and Parkinson's disease
   

Laser surgery (source: MRC Systems)

In refractive corneal surgery, femtonics replaces mechanical operations with scalpel and enables complication-reduced correction of the eye. The market potential for this application of femtonics is already 300 million Euro each year.

1.5 percent of all newborn babies are partially or totally deaf because their ossicles are stiffened. A femtosecond laser now makes it possible to dissolve such stiffening without destroying the ossicles which are of a size below one millimetre.

Dental caries can be removed painlessly and gently by means of femtonics. Gently means free of micro-cracks - one of the causes of the typical secondary caries prevailing today. The possible savings for the healthcare system are estimated at one billion Euro each year.

Selective dental caries removal with the femtosecond laser (source: A. Kasenbacher)

Objectives and measures

In 2000 already, the BMBF launched the "Femtosecond Technology" funding initiative because of the great significance of this key technology. About 30 million Euro have been made available for this initiative. Different applications in the areas of production, life sciences and measuring technology could successfully be demonstrated for the first time within the framework of the funding measure.

Studying and implementing the femtosecond technology promises to become a major, lasting contribution to the competitiveness of Germany as an industrial location. With its "Femtonics - Use of Ultra-fast Phenomena" funding measure, the BMBF continues its extremely successful first funding phase. Over the next three years, about 25 million Euro will be available for femtonics in research projects under industrial leadership.

The funding objective is to enhance Germany's leadership position in the area of laser technology and lasting cooperation between science and industry in the competitive translation of excellent results from basic research.