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This work deals with a theoretical study of the effect of pressure and temperature on the electronic states induced by the presence of a material defect in ZnO/Zn1-XMgxO Multi-Quantum wells. To determine the transmission coefficient of our structure, we use a mathematical language very well known for composite materials that of the response theory, also called the green function. We demonstrate that the insertion of a material defect in the middle of the MQWs allows our systems to be like symmetrical systems and amplifies the electronic transmission of the defect state. Moreover, we found that the hydrostatic pressure increase induces a noticeable shift of the electronic state towards the lower energies due to the increase of the effective mass. This behavior will be reversed for the increase in the temperature. Our results were validated and compared with those of the literature. The change of position of the defect state allows us to use this structure as a regulable pressure and temperature sensor.

This work investigates the behavior of the electronic states in ZnO/ Zn1-xMgxO MQWs induced by a staircase-like defect layer bounded by two substrates of the same type (ZnO). We use the interface response theory to calculate the different physical properties of the system. First, westudied a material staircase defect containing three material defects, such where the concentration depends on an increasing step noted P and a parameter X0 which does not exceed 0.35, so that the materials remain crystallized in the same structure. We found that the increase of these parameters induces an augmentation in the potential energy, leading to shifts of the electronic states to higher energies. In the second part, we studied the effect of introducing a geo-material defect with the step P=0.05 and X0=0 as optimal values, and the thickness of the staircase defect layer depends on an increment step noted S. We found that the variation of S influences the number of states that appear in the gap, which gives the possibility to improve the electron transport without using higher energy.Finally, we try to find several staircase defect configurations used in different structures. We found that inside the case of symmetric defect permutation, the position of the defect does not influence the behavior of the electronic states. Still, in the case of antisymmetric permutation, the position of thedefect has an influence on the behavior of the electronic states.