A theoretical study for temperature effects on the dominant color in colloidal nano sphere solutions

Abstract

The effects of the electron temperature on the dominant color in colloidal nano sphere solutions are analytically studied. This system contains ions (as radiators) close to the hot nano plasma spheres (HNPSs). Considering two separate models of the point radiated ions and applying the fluid dynamic equations and suitable Green’s function, the optical resonance of HNPSs is declared. The thermal effects in HNPSs show that a series of optical resonances occur in the system and the dominant resonance frequencies depend on the plasma geometry, electron density, electron temperature. The resonance frequencies in the two different models are exactly identical. Also, a new type of resonance frequency (subsidiary resonance frequencies), resulting in the thermal effects, is seen by considering two radiators beside the HNPS and, in this case, due to the sign of the ion radiators with same strengths, the even or odd modes are excited, separately. In other words, the permissible resonance frequencies in colloidal nano sphere solutions are categorized into two principal types: dominant resonance frequencies and subsidiary resonance frequencies. In addition, the graphs of the scattering patterns and resonance frequencies of this problem are analyzed. All of the resonance frequencies are varied with the temperature so that decreasing the Debye length (temperature) of HNPSs decreases the resonant frequencies and changes the dominant color of the system. Moreover, the dominant color of the system depends on the number of spheres in a colloidal solution including many bodies of nanospheres with different radii.