We evaluate the terahertz (THz) detectors based on field-effect transistor (FET) with graphene channel (GC) and a floating metal gate (MG) separated from GC by black-phosphorus (b-P) or black-arsenic (b-As) barrier layer. The operation of these GC-FETs is associated heating two-dimensional electron gas in impinging THz radiation leading to thermionic emission hot electrons MG. This results vari...

A 60 keV neutral Lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on KSTAR. The measurement will be the complementary of the heating beam based emission spectroscopy system which was built up in 2012, using the same observation system with different interference filters. The electron density and its fluctuation, thus the density distributio...

Thin films based on aluminum nitride were obtained by fs-laser assisted Pulsed Laser Deposition (fs-PLD) at room temperature tantalum substrates for studying the electron emission performance in range 700- 1600 °C, so to investigate possibility of their exploitation as thermionic cathodes. Results structural, chemical and morphological analyses show growth nanostructured thin with a significant...

A graphene Schottky contact was fabricated on an AlGaN/GaN heterostructure and subsequently analyzed. The calculated experimentally measured barrier heights (SBHs) determined using the theoretical Schottky–Mott model, thermionic emission temperature-dependent current–voltage measurement, capacitance–voltage measurement were observed to be inconsistent, which attributed ambiguities in both area ...

Seeking for thermoelectric (TE) materials with high figure of merit (or ZT), which can directly converts low-grade wasted heat (400 to 500 K) into electricity, has been a big challenge. Inspired by the concept of multilayer thermionic devices, we propose and design a solid-state thermionic devices (as a power generator or a refrigerator) in using van der Waals (vdW) heterostructure sandwiched b...

A microinsulation concept has been designed for use in MEMS devices. The design is carried out in the context of a thermionic microbattery, which converts the decay heat from radioactive isotopes directly to electricity using a vacuum thermionic diode. The role of the microinsulation is to maintain the isotope source temperature high in order to maintain good conversion efficiency. This paper p...