In order to implement complementary logic function with L-shaped tunneling field-effect transistors (TFETs), current drivability and subthreshold swing (SS) need to be improved more. For this purpose, highk material such as hafnium dioxide (HfO2) has been used as gate dielectric rather than silicon dioxide (SiO2). The effects of device parameters on performance have been investigated and the de...

We report theoretical study of the effects of energy relaxation on the tunneling current through the oxide layer of a two-dimensional graphene field-effect transistor. In the channel, when three-dimensional electron thermal motion is considered in the Schrödinger equation, the gate leakage current at a given oxide field largely increases with the channel electric field, electron mobility, and e...

A TFET has been considered as one of the most promising candidates for a next-generation electron device. It is because the SS of TFETs can be smaller than 60 mV/dec at room temperature, which is the physical limit of MOSFETs. Also, TFETs are immune to short channel effects thanks to their low Ioff. Especially, for the accurate evaluation and prediction of the electrical characteristics of TFET...

This study investigated the vault settlement characteristics of an unsymmetrically loaded tunnel which was excavated by annular excavation via core rock support method. Response surface methodology (RSM) was employed to design the experiments, evaluate the results with the purpose of optimizing the value of design parameters for reducing the vault settlement. The parameters such as horizontal d...

We solve the Dirac equation in two spatial dimensions in the setting of resonant tunneling, where the system consists of two symmetric cavities connected by a finite potential barrier. The shape of the cavities can be chosen to yield both regular and chaotic dynamics in the classical limit. We find that certain pointer states about classical periodic orbits can exist, which suppress quantum tun...

Nanowire band-to-band tunneling field-effect transistors ͑TFETs͒ are simulated using the Wentzel– Kramers–Brillouin ͑WKB͒ approximation and an atomistic, full-band quantum transport solver including direct and phonon-assisted tunneling ͑PAT͒. It is found that the WKB approximation properly works if one single imaginary path connecting the valence band ͑VB͒ and the conduction band ͑CB͒ dominates the tunne...

Multiferroic tunneling junction based four-state non-volatile memories are very promising for future memory industry since this kind of memories hold the advantages of not only the higher density by scaling down memory cell but also the function of magnetically written and electrically reading. In this work, we demonstrate a success of this four-state memory in a material system of NiFe/BaTiO3/...

Vertical graphene heterostructures have been introduced as an alternative architecture for electronic devices by using quantum tunneling. Here, we present that the current on/off ratio of vertical graphene field-effect transistors is enhanced by using an armchair graphene nanoribbon as an electrode. Moreover, we report spin-dependent tunneling current of the graphene/MoS2 heterostructures. When...

We report a low temperature measurement technique and the magnetization data of a quantum molecular spin, by implementing an on-chip SQUID technique. This technique enables SQUID magnetometry in high magnetic fields, up to 7 T. The main challenges and the calibration process are detailed. The measurement protocol is used to observe quantum tunneling jumps of the S = 10 molecular magnet, Mn(12)-...