Nanotechnology 24 (2013) 115306
M Stach et al
Figure 5. SEM images of nanowires strained at (a) x = 0% or y = 0%, (b) x = 8% or y = -3.8%, and (c) x = 25% or y = -8.1%
with their corresponding TTE, TTM, and ER values shown in (d)­(f), respectively. The pitch of the nanowires gradually decreased and the
TTE and TTM changed accordingly.
5. Results and discussion
WGP could explain the polarization characteristics. Figure 1
shows that the pitch and the linewidth decreased as the
The transmittance spectra of before- and after-straining
strain in the x-direction increased. Three strain polarization
samples were measured using a spectrophotometer (Jasco, V-
characteristics were demonstrated using the same WGP
570) at wavelengths ranging from 300 to 1000 nm with a beam
structure for comparison.
size of 5 mm. The after-strained WGPs were released from
Figures 5(a)­(c) respectively show scanning electron
the micropositioning system and placed for 1 h to achieve
microscope (SEM) images of the WGP with applied y of
a stable state before the spectrophotometer measurement.
0, -3.8 and -8.1%. Figures 5(d)­(f) respectively show the
The spectrophotometer setup consisted of a commercially
corresponding transmittances and ER values. The average ER
available Glan­Thompson polarizer [35] and the WGP
was 2.3 dB in the visible region when y = 0%. Conversely,
(figure 4). The transmittance readout produced by rotating the
the WGP after slight strain (y = -3.8%) in the plastic region
4

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