Essays about: "quantum point contact"
Showing result 11 - 14 of 14 essays containing the words quantum point contact.
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11. Quantized Transmission in an Asymmetrically Biased Quantum Point Contact
University essay from Linköpings universitet/Teoretisk FysikAbstract : In this project work we have studied how a two-dimensional electron gas (2DEG) in a GaAs/AlGaAs semiconductor heterostructure can be locally confined down to a narrow bottleneck constriction called a quantum point contact (QPC) and form an artificial quantum wire using a split-gate technique by application of negative bias voltages. The electron transport through the QPC and how asymmetric loading of bias voltages affects the nature of quantized conductance were studied. READ MORE
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12. Electron transport in quantum point contacts : A theoretical study
University essay from Institutionen för datavetenskap, fysik och matematik, DFMAbstract : Electron transport in mesoscopic systems, such as quantum point contacts and Aharonov-Bohm rings are investigated numerically in a tight-binding language with a recursive Green's function algorithm. The simulation reveals among other things the quantized nature of the conductance in point contacts, the Hall conductance, the decreasing sensitivity to scattering impurities in a magnetic field, and the periodic magnetoconductance in an Aharonov-Bohm ring. READ MORE
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13. Quantum point contact : A theoretical study
University essay from Matematiska och systemtekniska institutionenAbstract : Experiments shows that the conductance of a quantum point contact is quantized in steps of 2e²/h, where e is the charge of the electron and h is Planck’s constant, and thereby Ohm’s law is not valid for nanostructures. By using the approximation method finite difference, the transmission for one-dimensional contacts and one- and two-dimensional potentials are investigated. READ MORE
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14. Modeling of nanostructures with complex source and drain
University essay from Institutionen för fysik, kemi och biologiAbstract : In this thesis we report on calculations for open quantum mechanical and certain microwave systems. The models refer to a quantum point contact and an electron cavity. We model this open system with an imaginary potential as source and drain, and use the finite difference method to make our calculations. READ MORE