Ultra-compact nonvolatile plasmonic phase change modulators and switches with dual electrical-optical functionality

Programmable photonic integrated circuits (PICs) are the foundation of on-chip optical technologies with the optical modulators being one of the main building blocks of such programmable PICs. However, most of the available modulators suffer from high power consumption, low response time and large footprint. Additionally, they show a large resistance modulation, thus they require high switching voltage. In consequence, they operate much above CMOS-compatible voltages of 1.2 V and with high insertion losses. Furthermore, the state and information they carry are lost once the power is turned off – so, they are volatile. Thus, realizing modulators and phase shifters that overcome all of those problems still remain a challenge. To overcome some of those limitations the nonvolatile phase change materials implemented in the plasmonic structures are proposed that can offer many advantages as a result of high electric field interaction with nonvolatile materials. Consequently, proposed here novel plasmonic nonvolatile switches can operate by phase modulation, absorption modulation, or both and under zero-static power. Thus, only 230 nm long active waveguide is needed to attain full π phase delay with an insertion loss of 0.12 dB. Apart from it, when operating by amplitude modulation an extinction ration exceeding 2.2 dB/μm can be achieved while an insertion loss is kept at 0.185 dB/μm. Furthermore, the heating mechanism can be based on the external heaters, internal heaters, electrical (memory) switching or optical switching mechanism what provide a lot of flexibility in terms of a design and requirements.