Finite element analysis of the effect of wetting layer on the electronic eigenstates of InP/InGaP pyramidal quantum dots solar cell

Abstract

The efficiency of quantum dot (QD) to convert sunlight to electricity is based on the principle of multiple exciton generation (MEG), such that a single photon produces more than one electron-hole pair. The zero-dimensional structure of QD leads to spatial confinement of electronic energies. The energy levels of electrons in QDs depends on their size – the smaller the quantum dot, the greater the amount of energy required to excite electrons to the next level. This allows quantum dots to be tuned to absorb different wavelengths of light just by changing their size. The tuning of band in Quantum dot (QD) structures offers potential applications in the field of photovoltaics and optoelectronic devices. In this paper, we have presented the finite element method simulation results of solar cell based on InP pyramidal QDs in an InGaP matrix. We have found the ground state energies using time independent Schrödinger equation (SE) with effective mass approximation. We show that ground state energies are affected by the dimension of the QDs as well as by the presence of a quantum well wetting layer associated with the QDs.