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An expert is a man who has made all the mistakes which can be made in a very narrow field.

Niels Bohr

Currently working on...

Smart materials, high pressure studies on metal phosphates

Phosphates are successfully used in motor oils as antiwear agents. They reduce wear by forming a protective metal phosphate film on the rubbing surface. The origin of the extraordinary antiwear properties of the phosphates remains a matter of debates for decades. Our research indicates that unique antiwear properties of the phosphate films might be related to their smart materials behavior. Low coordination metal phosphates create open networks, which remain soft at low loads and stiffen rapidly upon loading. Material exhibiting such a "smart" effect can replace a system of layers of "normal" materials with increasing stiffness. Exploring the concept of smart materials behavior we gain confidence in finding new materials that can be used as prototypes of new generation additives.

A novel method for measurement of ultra-low wear rates

Measurement of ultra-low wear rates below 10 nm/h requires use of radioactive tracers. Up to date there was no alternative for the latter approach. The novel method utilizes application of gold markers, which are carefully implanted into specimen to detect minute material loss. Besides the accurate measurement of average wear (detection limits of 2 nm) new method allows for determination of spatially resolved wear with resolution better than 2 microns.

High pressure studies on germanium-antimony compounds

Phase change materials are class of materials, which can remain stable in a crystal or amorphous phase at ambient conditions requiring a significant amount of heat for a phase change. PCMs are gaining application in memory devices, where a bit of information is stored by changing the phase of a material region with help of heat, long pulse - recrystallization, short pulse - amorphization. We found that interconversion between phases could also be done by application of stress field. Compressive stress converts glass into crystal and tensile stress can convert crystal back into glass. Stress- induced interconversion does not impair the material as much as the heat-induced protocol. Stress conversion can also be faster, which allows to design highly efficient memory devices with high areal density.