Electric Transport in Materials at Microwave Frequencies

At microwave frequencies (a ), electric transport in materials (including interfaces) is determined by the dielectric function 

The relative reflected microwave power is (S is a proportionality factor)  

The real part describes the change in the phase factor (A/ ), which depends on the change in the dielectric constant (er) responsible for the phase shift. The change in the reflected microwave power as a consequence of an imposed potential change can therefore be written [by rewriting relation (6) with A as the proportionality constant]  

Although the conductivity change Aa [relation (8)] of microwave conductivity measurements and the Ac of electrochemical measurements [relation (1)] are typically not identical (owing to the theoretically accessible frequency dependence of the quantities involved), the analogy between relations (1) and (8) shows that similar parameters are addressed by (photo)electrochemical and photoinduced microwave conductivity measurements. This includes the dynamics of charge carriers and dipoles, photoeffects, flat band and capacitive behavior, and the effect of surface states. 

When two different experimental techniques are measuring the same variables (electronic charge carriers, dipoles) it is hoped that the combined 

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