Electrostatic Mechanism of Emission Enhancement in Hybrid Metal-semiconductor Light-emitting Heterostructures Page: 76

must produce some change in the distribution of carriers within the QW, we expect that
the image charge effect must alter the probability of recombination producing phonons,
and hence alter the intensity of the phonon replicas.
Figure 5.10 shows the Huang-Rhys parameter S as well as the intensity of the
main emission and its two phonon replicas. It is clear that there is significant exchange
of emission intensity in the Au NP sample to the primary emission from the first phonon
replica between 15 and 35 This switch lines up with a significant change in the value
of S from of 0.15 to ~0.5. This contrasts strongly with both the reference system, which
has a smaller overall change in S, and experiences less exchange in emission between
peaks, and the Ag sample, whose behavior seems to be the antithesis of the Au NP
20
-15
10
5--7
E - --- -- -- - - - -
-95
0 30 60 90
-6 50
-170
-190
-210
0 30 60 90
0 (Degrees)
Figure 5.11 a, Emission energy of the main emission for reference (black), Ag (blue)
and Au (red) measured as a deviation from the reference emission energy of 2.984
eV. b, Emission energy of the first phonon-replica, c, Emission energy of the second
phonon replica. The black dashed lines represent the uncorrected energies of the
three peaks. The black dot-dashed lines represent the energies of the phonon
replicas corrected for their temperature dependence. The gray shaded region
represents missing values replaced by interpolation with a spline.

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