David K. Ferry

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We present an efficient, fully quantum mechanical approach to calculating ballistic transport in fully-depleted silicon-on-insulator metal-oxide semiconductor field effect transistor devices in three dimensions and apply the technique to the calculation of threshold voltages for realistic devices with narrow channels. We illustrate the fact that each dopant(More)
As transistors get smaller, the simulations require full quantum-mechanical treatments. Most such approaches have treated the transport as ballistic, ignoring the scattering that is known to occur in such devices. We present the results of a three-dimensional, self-consistent quantum simulation of a silicon nanowire transistor. In these simulations we have(More)
We argue that many major features in electronic transport in realistic quantum dots are not explainable by the usual semiclassical approach, due to the contributions of the quantum-mechanical tunneling of the electrons through the Kolmogorov-Arnol'd-Moser islands. We show that dynamical tunneling gives rise to a set of resonances characterized by two(More)
Using a recursive scattering matrix variant, we examine the effects of discrete dopants on the threshold voltage of ultrasmall fully depleted SOI MOSFETs. We find that more highly doped channels produce more interference than do more lightly doped channels. This causes larger fluctuations in threshold voltage. Further, we find that the location of the(More)
The concentrations of wave functions about classical periodic orbits, or quantum scars, are a fundamental phenomenon in physics. An open question is whether scarring can occur in relativistic quantum systems. To address this question, we investigate confinements made of graphene whose classical dynamics are chaotic and find unequivocal evidence of(More)
We present the results of a three-dimensional, self-consistent ballistic quantum mechanical simulation of an indium arsenide ͑InAs͒ quantum wire metal oxide semiconductor field effect transistor with channel lengths of 30 and 10 nm. We find that both devices exhibit exceptional I on / I off ratio, reasonable subthreshold swing, and reduced threshold voltage(More)
—As scaling and performance needs of industry has continued, silicon-on-insulator technology appears to be a viable option. However, the small sizes of these structures require a quantum treatment for the transport. In this paper, we present results from a full three-dimensional (3-D) quantum simulation and describe the effects of quantum interference and(More)
—Within the next decade, it is predicted that we will reach the limits of silicon scaling as it is currently defined. Of the new devices under investigation, one of the most promising is the tri-gate quantum-wire transistor. In this paper, we study the role quantum interference plays in the operation of this device both in the ballistic and quasi-ballistic(More)