Silicon Atomic Quantum Dots Enable Beyond-CMOS Electronics - Field-Coupled Nanocomputing: Paradigms, Progress, and Perspectives - page 45

fabricated will include either of those reactive DB pairings. All of the DB cell
structures will involve DBs spaced by approximately 8 A, or more.
6 The ASiQD as a New Element: Building Molecules
Our primary focus is on ultra low power, ultra fast field controlled computing
as embodied by the QCA architecture or a variant thereof. We are well aware
though of multiple other possibilities created by the ASiQDs. It is like having a
new element to build with.
Fig. 13. A collection of diverse assemblies or molecules composed of atomic silicon
quantum dots. The three-atom structures in (a) and (b) have slightly differently spac-
ing. Different electronic structure results. The widely spaced grouping has a distinct,
less negative (brighter appearing) central atom while within the tightly spaced assem-
bly all atoms appear the same. The wider spaced molecule attains a larger negative
charge compared to the tightly spaced molecule. The latter has one electron. The
widely spaced molecule has two electrons and those repel one another, leaving the
central atom approximately neutral on average, and brighter in appearance. (c) Is an
image of a linear chain of ASiQDs. Such a structure will delocalize charge and allow
biasing wires to be fabricated where needed. The complex arrangement labeled (d) uses
both tunnel coupled atoms and perturbing atoms on the periphery to locally change
the character of individual atoms and thereby the properties of whole ensemble. The
perturbing atoms approximate the varied effects of different functional groups as used
to tune organic molecular properties.
Figure 13 shows a collection of diverse assemblies or molecules [ 12 ]. The three-
atom structures in (a) and (b) have slightly differently spacing. It is clear that
different electronic structure results. The widely spaced grouping has distinct,
less negative (brighter appearing) central atom while within the tightly spaced
assembly all atoms appear the same. An in depth discussion is outside of our
present scope. We will only note that the key difference between these structures