Strongly nonlinear problem of infinite order with L1L^1 data

In this paper, we prove the existence of solutions for the strongly nonlinear equation of the type $$Au+g(x,u)=f$$ where $A$ is an elliptic operator of infinite order from a functional space of Sobolev type to its dual. $g(x,s)$ is a lower order term satisfying essentially a sign condition on $s$ and the second term $f$ belongs to $L^1(\Omega).

Electrical properties of Cu 2 Zn(Sn 1−x Si x )S 4 ( x = 0.1, x = 0.4) compounds for absorber materials in solar-cells

International audienc

Structural and electrical properties of Cu2Zn(Sn1−xSix)S4 (x=0, x=0.5) materials for photovoltaic applications

International audienceThis work studied the electrical effects of the substitution of tin with silicon on p-type Cu 2 ZnSnS 4 semiconductor compounds. To this purpose, two samples, namely Cu 2 ZnSnS 4 and Cu 2 ZnSn 0.5 Si 0.5 S 4 , were prepared. The samples purities and homogeneities were characterized by both Energy Dispersive X-ray (EDX) spectroscopy and powder X-ray diffraction (PXRD). We observed that the temperature dependence of the electrical conductivity of materials exhibits a crossover from T À1/4 to T À1 dependence in the temperature range between 130 and 140 K. The characteristic temperature (T 0,Mott), the hopping distance (R hop), the average hopping energy (D hop), the localization length (n) and the density of states (N(E F)), were determined, and their values were discussed within the models describing conductivity in p-type semiconductor