Chalcogenide phase change materials(PCMs)have been extensively applied in data storage,and they are now being proposed for high resolution displays,holographic displays,reprogrammable photonics,and all-optical neural ...Chalcogenide phase change materials(PCMs)have been extensively applied in data storage,and they are now being proposed for high resolution displays,holographic displays,reprogrammable photonics,and all-optical neural networks.These wide-ranging applications all exploit the radical property contrast between the PCMs’different structural phases,extremely fast switching speed,long-term stability,and low energy consumption.Designing PCM photonic devices requires an accurate model to predict the response of the device during phase transitions.Here,we describe an approach that accurately predicts the microstructure and optical response of phase change materials during laser induced heating.The framework couples the Gillespie Cellular Automata approach for modelling phase transitions with effective medium theory and Fresnel equations.The accuracy of the approach is verified by comparing the PCM’s optical response and microstructure evolution with the results of nanosecond laser switching experiments.We anticipate that this approach to simulating the switching response of PCMs will become an important component for designing and simulating programmable photonics devices.The method is particularly important for predicting the multi-level optical response of PCMs,which is important for all-optical neural networks and PCM-programmable perceptrons.展开更多
基金This research was supported by the NSLM project(A18A7b0058)Support from A*STAR’s microscopy facility is kindly acknowledged.Ms Ning is grateful for her Singapore Ministry of Education(MoE)PhD scholarship.We are thankful for the compute time granted by the National Supercomputing Centre(NSCC)Singapore.The work was carried out under the auspices of the SUTD-MIT International Design Center(IDC).
文摘Chalcogenide phase change materials(PCMs)have been extensively applied in data storage,and they are now being proposed for high resolution displays,holographic displays,reprogrammable photonics,and all-optical neural networks.These wide-ranging applications all exploit the radical property contrast between the PCMs’different structural phases,extremely fast switching speed,long-term stability,and low energy consumption.Designing PCM photonic devices requires an accurate model to predict the response of the device during phase transitions.Here,we describe an approach that accurately predicts the microstructure and optical response of phase change materials during laser induced heating.The framework couples the Gillespie Cellular Automata approach for modelling phase transitions with effective medium theory and Fresnel equations.The accuracy of the approach is verified by comparing the PCM’s optical response and microstructure evolution with the results of nanosecond laser switching experiments.We anticipate that this approach to simulating the switching response of PCMs will become an important component for designing and simulating programmable photonics devices.The method is particularly important for predicting the multi-level optical response of PCMs,which is important for all-optical neural networks and PCM-programmable perceptrons.
