Science Advances reports Jiasen Zhang and collaborators¡¯ work on electrically driven monolithic subwavelength plasmonic interconnect circuits

On-chip electrically-driven miniaturized optoelectronic integrated circuits (OEICs) that combine the high bandwidth of a photonic network with the compactness of an electronic circuit are actively pursued in the post-Moore era to realize rapid data transmission and powerful signal processing. Therefore, considerable research efforts over the past several decades have been devoted to fabricate OEICs with silicon, germanium, II-VI and III-V semiconductors, nanowires and an expanding class of two-dimensional materials in the past decades. Nevertheless, none of these works have been demonstrated at the complete circuit level to enable photonics to monolithically interface with electronics with the same feature size.

Recently, Prof. Jiasen Zhang and his collaborators, Prof. Lianmao Peng¡¯s group, from the School of Electronics Engineering and Computer Science, and Prof. Huaping Liu¡¯s group, from the Institute of Physics, Chinese Academy of Science, demonstrated a monolithic plasmonic interconnect circuit (PIC) consisting of a photovoltaic cascading detector, Au-strip waveguides and electrically-driven surface plasmon polariton (SPP) sources. These components are fabricated from carbon nanotubes (CNTs) via a CMOS-compatible doping-free technique in the same feature size, which can be reduced to deep-subwavelength scale (~¦Ë/7 to ¦Ë/95, ¦Ë=1,340 nm) compared with the 14-nm technique node. An OEIC could potentially be configured as a repeater for data transport because of its ¡°photovoltaic¡± operation mode to transform SPP energy directly into electricity to drive subsequent electronic circuits. Moreover, chip-scale throughput capability has also been demonstrated by fabricating a 20¡Á20 PIC array on a 10¡Á10 mm2 wafer. Tailoring photonics for monolithic integration with electronics beyond the diffraction limit opens a new era of chip-level nanoscale electronic-photonic systems, introducing a new path to innovate towards much faster, smaller and cheaper computing frameworks.

Electrically driven plasmonic interconnect circuit system based on carbon nanotubes. The inset shows the mode distribution of a 500-nm-wide Au-strip waveguide. Scale bar, 500 nm.	Chip-level integration of the plasmonic interconnect circuits. Scale bar, 40¦Ìm.

This work has been published on Science Advances (Science Advances 3, e1701456 (2017)). IEEE Spectrum devoted a special report on the work with a title of ¡°Carbon Nanotubes Make Big Push in Plasmonic Circuits¡±.