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A highly ordered structure and a relatively simple method of obtaining porous anodic alumina (PAA) have been
attracting the attention of researchers to the potentialities of using such material in various fields of science and
technology. The PAA- technology is oriented to mass production, does not require the use of expensive modern
lithography and evaporation equipment. The technology makes it possible to produce PAA layers in a wide thickness
range (0.1 - 800 μm) and with a spatially ordered system of pores whose diameter and periodicity can be changed within
the range from tens to hundreds of nanometers. By filling nanopores with conductive, semiconductive and dielectric
materials or their combinations, possibilities arise of making micro-sensors based on various physical, chemical and
biological effects. For numerous applications, there is a promising development direction associated with modification of
PAA structures with nano-diamonds. To control the modification process and for subsequent use of films in energyabsorbing
sensor systems, a real-time measurement is required of their thermal and physical parameters, and, in
particular, the coefficient of thermal diffusion (CTD).
In this report an optical method for determining CTD is developed which is based on an analysis of the spatialtemporal
dynamics of the speckle field. The proposed method for measuring the coefficient of thermal diffusion is based
on the measurement of an average speed of the speckle-field movement along the specimen surface. Due to statistical
nature of speckles, their movement must be also described statistically. Our approach consists in the use of correlation
functions describing the degree of change in a speckle-image of some element of the surface in the process of heating or
cooling. The proposed method is fully optical, fast, non-invasive and can be customized for specific applications. Optical
measurement of CTD has been carried out for PAA structures both modified and not modified with nano-diamonds.
High resolution allows one to measure spatial inhomogeneities of thermophysical properties of PAA- films.
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