Ultrafast All-Optical Serial-to-Parallel Converters Based on Spin-Polarized Surface-Normal Optical Switches

We describe our recent work on all-optical serial-to-parallel converters (SPCs), from the all-optical switches employed in the SPCs to the application of the SPCs for packet processing. The ability to handle ultrafast optical signals is enabled by types of surface-normal optical switches employing different switching mechanisms: one is based on rapid electron trapping in low-temperature-grown Be-doped quantum wells, and the other is based on differential spin-excitation. With these switches, 1:16 SPCs are demonstrated for 40-Gbit/s, 100-Gbit/s, and 1-Tbit/s optical packets. In addition, the SPC is compact, low power, polarization insensitive, exhibits extremely high on/off ratios, and generates a simultaneous parallel output, and thus, provides a promising interface device allowing the processing of ultrafast, asynchronous optical packets in a highly functional complementary metal-oxide-semiconductor (CMOS) processor. As an application, an optical label swapper that integrates the SPC with a CMOS processor is also demonstrated for 40-Gbit/s asynchronous optical packets