Research progress on free-space-wave add/drop multiplexing for WDM optical-interconnect system in packaging

Integrated-optic devices enabling intra-board chip-to-chip optical interconnection with tens-terabit-per-second transmission bandwidth from two-dimensional (2D) array of vertical-cavity surface-emitting lasers to 2D array of photodiodes are reviewed. Design strategy and preliminary experimental results on wavelength-division-multiplexing signal transmission are also presented and discussed.