The effect of rashba spin–orbit interaction on optical far-infrared transition of tuned quantum dot/ring systems

In the present work, optical properties of tuned quantum dot/ring systems with considering the effect of Rashba spin–orbit interaction are theoretically investigated. To this end, we describe our system by using an appropriate model potential to obtain the energy levels and wave functions analytically. The system is excited by a monochromatic electromagnetic field and intersubband transitions for the electrons are considered. Then, analytical expressions for optical absorption coefficients and refractive index changes are used. The effect of quantum dot radius and the Rashba coupling constant on the optical properties have been investigated. The results show that: (i) The effect of Rashba spin–orbit interaction on the peak values of the refractive index changes is negligible. (ii) The total absorption coefficient is enhanced and shift toward higher energies with considering the effect of Rashba spin–orbit interaction. (iii) The impact rate of spin–orbit interaction on the optical properties relates to the quantum dot radius, depth of confining potential and the Rashba coupling constant.