Continuous Broadband MWP True-Time Delay With PbS-PMMA and PbS-SU8 Waveguides

Abstract

A new microwave true-time delay (TTD) photonic unit based on the dispersion of PbS colloidal quantum dots (QDs) in a Polymethyl methacrylate (PMMA) and the SU8 photoresist is presented. With this aim, the PbS-PMMA and PbS-SU8 nanocomposites are integrated on a silicon platform in the form of a planar and ridge waveguides, respectively. When PbS QDs on those structures are pumped below their band-gap, a phase shift and a temporal delay in an optically conveyed (at 1550 nm) microwave signal is performed. The results of these devices show potential benefits over current TTD technologies, since the proposed photonic waveguide structures allows real-time adjustment of the temporal delay by tuning the power of the pumping signal, more than 3.5 ps over 25 GHz, and a high level of integration due to the novel proposed photonic waveguide structures and the materials used.

Field Manipulations in On-Chip Micro/Nanoscale Lasers Based on Colloid Nanocrystals

“…These SU-8 patterns functioned as waveguides for both the pump and signal beams, with minimal absorption losses. In 2016, the research group continued to improve the design of the double-layer waveguide, proposing a bilayer structure composed of an SU8 layer and a PbS QDs layer as well as a two-dimensional ridge waveguide composed of an SU8 cladding layer [110]. This reduced the propagation loss to a total optical loss of 22 dB.…”

“…Copyright 2013, IEEE; Reprinted with permission from Ref. [110]. Copyright 2016, IEEE; Reprinted with permission from Ref.…”