Near-field radiative heat transfer between shifted graphene gratings
Physical Review B(2024)
Abstract
We examine the near-field radiative heat transfer between finite-thickness
planar fused silica slabs covered with graphene gratings, through the
utilization of the exact Fourier modal method augmented with local basis
functions (FMM-LBF), with focus on the lateral shift effect. To do so, we
propose and validate a minor modification of the FMM-LBF theory to account for
the lateral shift. This approach goes far beyond the effective medium
approximation because this latter cannot account for the lateral shift. We show
that the heat flux can exhibit significant oscillations with the lateral shift
and, at short separation, it can experience up to a 60
to the aligned case. Such a lateral shift effect is found to be sensitive to
the geometric factor d/D (separation distance to grating period ratio). When
d/D>2 (realized through large separation or small grating period), the two
graphene gratings see each other as an effective whole rather than in detail,
and thus the lateral shift effect on heat transfer becomes less important.
Therefore, we can clearly distinguish two asymptotic regimes for radiative heat
transfer: the LSE (Lateral Shift Effect) regime, where a significant lateral
shift effect is observed, and the non-LSE regime, where this effect is
negligible. Furthermore, regardless of the lateral shift, the radiative heat
flux shows an obvious and non-monotonic dependence on the graphene chemical
potential. That is, we can get an optimal radiative heat flux (peaking at about
0.3eV chemical potential) by in situ modulating the chemical
potential. This work has the potential to unveil new avenues for harnessing the
lateral shift effect on radiative heat transfer in graphene-based nanodevices.
MoreTranslated text
AI Read Science
Must-Reading Tree
Example
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined