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Full-Text Articles in Materials Science and Engineering
Sub-Bandgap Photon-Assisted Electron Trapping And Detrapping In Algan/Gan Heterostructure Field-Effect Transistors, Andrew Gunn
Sub-Bandgap Photon-Assisted Electron Trapping And Detrapping In Algan/Gan Heterostructure Field-Effect Transistors, Andrew Gunn
All Theses
We have investigated photon-assisted trapping and detrapping of electrons injected from the gate under negative bias in a heterostructure field-effect transistor (HFET). The electron injection rate from the gate was found to be dramatically affected by sub-bandgap laser illumination. The trapped electrons reduced the two-dimensional electron gas (2DEG) density at the AlGaN/GaN heterointerface but could also be emitted from their trap states by sub-bandgap photons, leading to a recovery of 2DEG density. The trapping and detrapping dynamics were found to be strongly dependent on the wavelength and focal position of the laser, as well as the gate bias stress time …
Inverse Problems Using Reduced Basis Method, Phil Gralla
Inverse Problems Using Reduced Basis Method, Phil Gralla
All Theses
Inverse Problems is a field of great interest for many applications, such as parameter identification and image reconstruction. The underlying models of inverse problems in many applications often involve Partial Differential Equations (PDEs). A Reduced Basis (RB) method for solving PDE based inverse problems is introduced in this thesis. The RB has been rigorously established as an efficient approach for solving PDEs in recent years. In this work, we investigate whether the RB method can be used as a regularization for solving ill-posed and nonlinear inverse problems using iterative methods. We rigorously analyze the RB method and prove convergence of …