The Study On Impurity In A Spherical Parabolic Quantum Dot With Temperature And Pressure

Low-dimensional semiconductor structures such as quantum wells, quantum wires,and quantum dots have become more and more important in the recent years due to theirfundamental properties and their wide range of applications. Among them, quantum dotswith different shapes such as rectangular, cubic, spherical, and disc-shaped have receivedmore attention from researchers. So, a large change in the dielectric constant of the hostmaterial takes place when incident photon energies are equal to the intersubband transitionenergies, which alters the index of refraction and absorption coefficient. With thescience-technology developed, more and more nano-materials will be applied widely in theelectro-optical devices. Therefore, it is important to study the optical and transportproperties of low-dimensional semiconductor structures. In the recent years, studies havebeen investigated on the optical properties of low-dimensional materials experimentally andtheoretically.We give a general statement of the properties and application of semiconductorquantum dot (SQD). The current state of researches on SQD and the main method weused in the thesis are also included in the first chapter.A detailed discussion about the bound energy and the oscillator strength of SQD in theelectric field is showed in the second chapter. The whole calculation is confined in themethod of effective mass approximation. Some meaningful results are being given out inthis chapter which include:1. The strong confinement condition the perturbation approximation based on.2. The bounded energy of the system.3. The formula of the energy spectrum of impurity state.4. The behavior of oscillator strength in different electric field density.In the chapter3, we discuss the optical properties of SQD in electric field influencedby pressure and temperature. According to density matrix theory. We subsequently arriveat the formula of refractive index of SQD. The influence of pressure and temperature onspherical SQD in electric field is then analysed.In the last chapter, we give out the conclusion and outlook.