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All-optical reconfigurable non-inverted logic gates with a single semiconductor optical amplifier (SOA) is proposed. Compared with the probe light of continuous light, the clock (Clk) pulse sequences light is regarded as the probe light so that the output of logic gates is a non-inverted code which is suitable to the further combination of different logic gates. The scheme is based on a single SOA with four-wave mixing and cross-gain modulation. Multiple functional logic operations are implemented and switched by adjusting the center wavelength of tunable optical band-pass filter without altering the experimental device. In the experiment, all-optical multiple logic gates with 10 Gb/s return-to-zero of NOT, NOR, XNOR, AND, A¯•B and A•B¯ are realized. Meanwhile, because Clk probe light is a small signal, a saturable absorber (SA) is configured to improve the extinction ratio (ER) and optical signal to noise ratio (OSNR). For logic gates NOT, NOR and XNOR with Clk probe light, ER and OSNR are only deteriorated by 1 dB with the SA. For logic gate AND with Clk probe light, ER is improved by about 2 dB based on four-wave mixing and OSNR keep the original values with the SA respectively. For logic gates A¯•B and A•B¯ without Clk probe light, ER and OSNR are both only deteriorated by 0.5 dB. It has the potential to obtain more complex combinational logic gates.

Sidewall profile reconstruction of microstructures with the high aspect ratio is a problem urgently to be solved in MEMS field. In this paper, a measuring method based on near-infrared light scanning interferometry (NILSI) is presented according to the transmission principle of semiconductor materials in the infrared light region. The NILSI is extended from the white light to near-infrared light and from surface profile reconstruction to sidewall profile reconstruction. The NILSI system is constituted by a near-infrared light source, an interference microscope, infrared CCD, piezoelectric ceramics (PZT) with high accuracy and the data acquisition system. The test sample is taken from GaAs microstructures with high aspect ratio and made by two different height steps for measuring with different typical testing equipment. Near-infrared light vertical scanning interference (NILVSI) is improved to compensate optical path difference (OPD) and the large surface roughness. The sidewall profile of the sample is obtained and compared with that of scanning electron microscopy (SEM) and white light scanning interferometry (WLSI). Test results demonstrate that the steps have 2.115 μm and 0.762 μm relative heights and 1.34 % and 2.14% relative errors respectively. There is a good agreement with the results of SEM and WLSI. The system can reconstruct the sidewall profile of microstructures with high aspect ratio.