Sumários

T10 - Coulomb blockade. Single electron transistor.

29 Novembro 2022, 14:00 • Maria Margarida Cruz

Transference through a barrier. Tunnel effect. A tunnel effect barrier seen as balli sticconductance with small transmission. Limit for barrier resistance to exist tunnel effect. Electrostatic energy and Coulomb blockade effect. Orthodox condition for an electron to be transfer across the barrier. Metallic island between two barriers in a canal - double barrier. Single electron tunneling. Asymmetric double barrier. Single electron transistor (SET). Representation Vgate as function of Vsource-drain- stability diagram (diamond diagram).

Problems 7b

22 Novembro 2022, 16:30 • Maria Margarida Cruz

Discussion of problems in 7th series.

T9 - Quantum Hall Effect

22 Novembro 2022, 14:00 • Maria Margarida Cruz

Multiplicity of Landau levels. Magnetic length. Relationship with magnetic flux. The chemical potential of two-dimensional electron gas with applied magnetic field.
Electrons in a parabolic confinement potential and subject to an intense magnetic field. charge transport along the boundaries. Localization of Landau states by impurities. Synthesis of the main aspects involved in Quantum Hall Effect. Presentations of the fractional quantum Hall effect.

Problems 7a

15 Novembro 2022, 16:30 • Maria Margarida Cruz

Discussion of problems in 7th series.

T8 - Electrons in a magnetic field

15 Novembro 2022, 14:00 • Maria Margarida Cruz

Hall Effect. Movement of free electrons in a magnetic field. Cyclotron frequency. Movement of free electrons under both normal magnetic and electric fields. Electrons in a solid (Bloch electrons) under normal magnetic and electric fields. Cyclotronic mass. Relationship between momentum and velocity in a magnetic field. Two-dimensional gas of electrons subject to a magnetic field. Landau levels.