Factors Influencing Energy Quantisation
AbstractDepartment of Physics, College of Science & Agriculture, University of Abuja, P. M. B. 117, Abuja FCT, Nigeria. Investigations of energy quantisation in a range of multiple quantum well (MQW) systems using effective mass band structure calculations including non-parabolicity in both the well and barrier layers are reported. Working with different values of band offsets and band gap differences, the results of the investigations show that energy quantisation is relatively more sensitive to band gap differences than to band offsets. For the particular case of the GaAs multiple quantum well systems, it is observed that while the 70:30 value of band offsets gave the best fit of theory to experiment for the electron-heavy hole transitions under parabolic band approximations, the electron-light hole transitions under the same parabolic band approximation support the 85:15 value. The inclusion of non-parabolicity however, supports values close to the 63:37 ratio. The factors observed to influence the confinement energies include the non consideration of the Key Words: Energy quantization, effective mass, band structure, non-parabolicity, band offsets, band gap.
(Global Journal of Pure and Applied Sciences: 2002 8(2): 271-278)