that a focused image can be obtained at the CCD camera. The objectives Ob1 and Ob2 were 20x Mitutoyo Plan Apo NIR infinity-corrected objectives with numerical apertures NA= 0.4 and focal lengths f = 200 mm. The objective Ob3 was a 10x objective of the same NA. The range of incident angles was reduced to±3oC by the iris before Ob1.
All the transmittance measured from this system are obtained by referring to the transmitted light in the unpatterned area in our samples.
Figure A.2:Schematic of the setup for transmittance measurements.A halogen illuminates system as light source.L1, L2, L3 and L4 are lens with 1 inch diameter of carefully chosen focal lengths. Ob1, Ob2 and Ob3 are objectives used as light condenser. P represents polarizer. The solid black lines mean irises. The dashed line is a removable mirror. Spectro here refers to spectrometer.
.
A.3
PL mapping setup
The photoluminescence (PL) mapping of the samples shown in this thesis were measured by a commercial WiTec-alpha300S system in confocal micro- scope configuration, the setup of this system is shown in Figure A.3. The ex- citation light source are coupled into the system through fibers and we could change excitation source depending on requirements. This system could be run in both reflection and transmission mode (we show transmission here). The PL scanning is enabled by the piezo scanner and the avalanche photo diode (APD) is used to detect the signal. In addition, the spectrometer also enable us to measure the spectral data.
Figure A.3: Setup for PL mapping. The tunable light source supports wavelengths in wide range from 500 nm to 900 nm. The filters could also be changed to fit with different purposes.
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