Estados eletrônicos, magnetização e corrente persistente em anéis e pontos quânticos controlados por curvatura e rotação

Abstract

We embark on an investigation of the effects of curvature and inertial forces in a non interacting spinless electron gas confined in mesoscopic systems. In the first case, the thin-layer quantization procedure is considered to study the physical implications due to curvature effects on the spectrum, magnetization, and persistent current of quantum rings and quantum dots both in the presence of external magnetic fields. In such procedure, it arises a geometry induced potential, which depends on both the mean and the Gaussian curvatures. For a ring with a mesoscopic size, the effects of the geometry potential on the energy spectrum are negligible. In magnetization, Aharonov-Bohm (AB) and Haas van Alphen(dHvA) oscillations are observed, while in persistent current only AB-type oscillations are observed. Both physical properties, curvature increases the amplitude of oscillations. On the other hand, at a quantum dot, among the various physical implications due to the curvature of the system, we can mention the absence of the state m = 0. This affects the Fermi energy and, consequently, the magnetization and the persistent current of the model. In the study of magnetization and persistent currents, we found that AB-type oscillations are present, while dHvA-type oscillations are not well defined. In the second case, we analyze how inertial effects can affect several properties of mesoscopic systems. Starting from the Schrödinger equation in a rotating frame, we describe the influence of noninertial effects on the physical properties of quantum rings, 1D and 2D, in the presence of a uniform magnetic field. For 1D quantum ring, we study how electronic states are affected by rotation, and then we investigate how persistent current and magnetization in the ring are influenced by temperature and rotation effects. AB-type oscillations are observed. For 2D quantum ring, we highlight that the potential used to describe the model implies in the appearance of edge states and Landau states (bulk states). It is known in the literature that bulk states do not carry current. As the most relevant case, we report that there is a current carried by the bulk states, which is due to the rotation of the ring.