A compact 64‐channel hybrid demultiplexer based on silicon‐on‐insulator nanowires is proposed and demonstrated experimentally to enable wavelength‐division‐multiplexing and mode‐division‐multiplexing simultaneously in order to realize an ultra‐large capacity on‐chip optical‐interconnect link. The present hybrid demultiplexer consists of a 4‐channel mode multiplexer constructed with cascaded asymmetrical directional‐couplers and two bi‐directional 17 × 17 arrayed‐waveguide gratings (AWGs) with 16 channels. Here each bi‐directional AWG is equivalent as two identical 1 × 16 AWGs. The measured excess loss and the crosstalk for the monolithically integrated 64‐channel hybrid demultiplexer are about ‐5 dB and ‐14 dB, respectively. Better performance can be achieved by minimizing the imperfections (particularly in AWGs) during the fabrication processes.
An investigation of the WIMP annual modulation signature is in progress at the Gran Sasso National Laboratory of the I.N.F.N.
by means of the kg NaI(Tl) DAMA set-up; the results obtained during four annual cycles have already been published. In this paper we will
further address in some details the main arguments, which have allowed us to exclude known systematic effects as a possible
source of the annual modulation observed in the rate at very low energy. In particular, the (more recently released) data
of the DAMA/NaI-3 and DAMA/NaI-4 running periods are considered as quantitative examples.
Received: 26 September 2000 / Published online: 27 November 2000 相似文献
