Environmental Engineering Reference
In-Depth Information
thermal conductance, without losing generality we will investigate
graphene junctionsthat have sharp interfaces.
3.4.3.2 Ribbon width
Three types of graphene-based devices are considered: single-
interface junctions, double-interface junctions and QDs, which are
composed of GNRs as shown in Fig. 3.15a. A simplified model of
QD is used here, characterized by a center part connected by two
narrow constrictions on the left and right. More realistic models of
QD will be discussed later. For these graphene-based nanodevices,
one of most important structural parameters is the ribbon width.
In this section, we study the influence of ribbon width on thermal
transport. The edge of composed GNRs is limited to be zigzag
here, and the influence of edge shape on thermal transport will
be studied by comparing with armchair edges. The two GNRs,
Figure 3.15
Schematics of graphene junctions and quantum dots formed
by
n
-ZGNR and
m
-ZGNR (
n
<
m
): single-interface junction “Z
n
-Z
m
”, double-
interface junction “Z
m
-Z
n
-Z
m
” and quantum dot “Z
n
-Z
m
-Z
n
”. (b) Thermal
conductance (
σ
) at 300 K as a function of structure parameter
m
for “Z8-
Z
m
” (circle), “Z
m
-Z8-Z
m
” (triangle) and “Z8-Z
m
-Z8” (diamond), (c) Thermal
conductance (
σ
), (d) thermal contact resistance (
R
C
), and (e) thermal
conductance ratio (
σ
/
σ
0
) at 300 K as a function of structure parameter
n
for pristine
n
-ZGNR (square),“Z
n
-Z18” (circle), “Z18-Z
n
-Z18”(triangle) and
“Z
n
-Z18-Z
n
”(diamond)[51].
