Micron-scale Raman amplifier: another progressive step towards the maturity of silicon photonics

Abstract

Notice of redundant publication "Micron-scale Raman amplifier: another progressive step towards the maturity of silicon photonics" It has been brought to the attention of the editors that this article contains redundancies when compared with an earlier article published by the authors in Datta T and Sen M 2017 Superlattices Microstruct. 109 107–16. The original article was not referenced. These concerns were identified after the article appeared as accepted but before publication of the final version. As a member of COPE this was been investigated in accordance with the COPE guidelines and it was agreed a notice of redundant publication should be applied. A new model for micron scale all-silicon amplifier has been proposed based on stimulated Raman scattering (SRS) in a slotted photonic crystal waveguide (SPCW). Silicon nanocrystal material is considered to be embedded in the slot of the SPCW to exploit its giant Raman gain coefficient. Moreover, the gain has further been enhanced by using the ultra-high optical confinement of the SPCW. Results of simulations show that the threshold power of a 3 μm long SPCW based Raman amplifier is in the order of merely 500 μW, while the CW Stokes is launched with a power of 50 μW. The simulations also show that a merely 1.5 μm long SPCW can offer ≈3 dB gain even at the 400 Gbps pulse repetition rate. However, pulse shape becomes disrupted by the SRS induced temporal broadening which has further been reduced considerably by operating the Stokes at a different resonance peak in the SRS gain spectrum. With these tremendous performances, the SPCW based Raman amplifier proves its potentiality for application in on-chip optical interconnects and also opens up a pavement for realizing the long desired micron-scale all-silicon Raman laser.