In this paper, electron emission from non-planar potential barrier structures is analyzed using a Monte Carlo electron transport model. Compared to the planar structures, about twice bigger emission current can be achieved for the non-planar tall barriers. The thermionic emission enhancement is attributed to combined effects of increased effective interface area and reduced probability of total...

A brief overview of the research activities at the Thermionic Energy Conversion (TEC) Center is given. The goal is to achieve direct thermal to electric energy conversion with >20% efficiency and >1W/cm power density at a hot side temperature of 300-650C. Thermionic emission in both vacuum and solid-state devices is investigated. In the case of solid-state devices, hot electron filtering using ...

Recent studies have predicted that heterostructure superlattices can enhance the effective thermoelectric power factor significantly through selective emission of hot carriers via thermionic emission. Here, we study the potential of SiGe/Si superlattices for power generation at high temperatures. A detailed theory based on Boltzmann transport equation is developed which takes into account multi...

Photoelectron velocity-map imaging and electronic structure calculations have been used to study the temporary anion (resonance) dynamics of the closed-shell site-specific deprotonated tetracene anion (C18H11(-)) in the hv = 3.26 eV (380 nm) to 4.13 eV (300 nm) range. In accord with a recent frequency-, angle-, and time-resolved photoelectron imaging study on a related but open-shell polyaromat...

We have measured the dependence of the Fermi energy on carrier concentration in Sn doped InGaAs at 4.2 K and 300 K. At 4.2 K the Fermi energy was measured by photoluminescence spectroscopy, and at 300 K it was deduced from transport measurements of thermionic emission. In both cases the dependence of the Fermi energy on the mobile electron concentration, measured by Hall effect, strongly deviat...

Direct reaction of herringbone, platelet, or narrow, tubular herringbone graphitic carbon nanofibers (GCNFs) with molten potassium gives K/GCNF intercalates with stoichiometric control of potassium loading. Intercalate formation is confirmed by powder X-ray diffraction and micro-Raman spectroscopy. K/GCNF intercalates act as radical-anion alkene polymerization catalysts and reduce water with st...

The metal-insulator-semiconductor (MIS) diode is the most useful device in the study of semiconductor surfaces. The current-voltage data of the metal-insulatorsemiconductor Schottky diode are simulated using thermionic emission diffusion equation taking into account the interfacial layer parameters. The calculated current–voltage data are fitted into ideal thermionic emission diffusion equation...

Thermionic energy conversion, a process that allows direct transformation of thermal to electrical energy, presents a means of efficient electrical power generation as the hot and cold side of the corresponding heat engine are separated by a vacuum gap. Conversion efficiencies approaching those of the Carnot cycle are possible if material parameters of the active elements at the converter, i.e....

A brief introduction to electron and ion sources for particle accelerators is given. Concentrating on the basic processes for the production of these particles, thermionic and photocathode production of electrons and the processes in Penning and electron cyclotron resonance ion sources are covered. Finally, negative ions are discussed.