Congratulations to Li Tian Chew, who gave an excellent presentation and successfully defended her Master’s degree work on next generation memory technologies. The screenshot shows the moment that Li Tian was informed that she had passed. Under difficult circumstances amid the COVID19 outbreak, Li Tian had to present her work to the international thesis committee using video conferencing. Li Tian is among the pioneering batch of students on the SUTD-CGU Dual Masters Degree program in Nano Electronics Engineering and Design (NEED). She will be awarded two masters degree certificates (one from SUTD and one from Chang Gung University in Taiwan).
Our paper, “Avalanche atomic switching in strain engineered Sb2Te3–GeTe interfacial phase-change memory cells” has been selected by the Nano Futures’ editors as a highlight of 2017. 12 papers from 2017 that highlight the novelty and exceptional standards of Nano Futures, were selected for the highlights collection. See here for more info.
Jitendra Kumar Behera, Xilin Zhou, Alok Ranjan, Robert Edwardsimpson:Optimisation of phase change van der Waals structures by statistical design of experiments
Li Tian Chew, Li Lu, Robert Simpson:Interfacial Damage in Phase Change Materials Tuned Optical Structures
Li Lu, Ramon Paniagua-Dominguez, Vytautas Valuckas, Arseniy I. Kuznetsov, Robert E. Simpson:Novel chalcogenide as a material platform for tunable nanoantenna arrays in the visible and near infrared spectrum
Jose Martinez, Weiling Dong, Robert Simpson:Optical response of chalcogenide phase-change materials
Jing Ning, Robert Simpson, Yee Kan Koh:Electrical, optical and thermal properties of Sb2Te3 and related materials.
Rob Simpson, Jitendra Behera, Janne Kallika, Xilin Zhou, “Active electronic and photonic materials by nanostructural design”
Congratulations to ACTAlab postdoc, Dr Xilin Zhou, for winning the best poster award at the Materials Research Society Spring Meeting, which was held in Phoenix USA April 2017. Xilin’s poster discusses the atomic transitions involved in Sb2Te-GeTe superlattices. In particular Xilin showed through a combination of experiments and simulations that the activation energy for disordering of the GeTe layers decreases as more atoms switch, and this leads to an avalanche switching effect.
There were more than 1500 posters presented at the conference, and only 9 were honored with a Best Poster Award. The photograph below shows Xilin with the meeting chairs.
Congratulations to ACTAlab PhD student, Ms Weiling Dong, for winning the best poster award at the EPCOS conference, which was held at Trinity College, Cambridge, UK 5th-6th Sept. Weiling’s poster discusses the combination of plasmonic nanogratings and the phase change material Ge2Sb2Te5 to create structural colour. More details of Weiling’s work can be found here.
Today, Xilin Zhou’s paper, which discusses how oxygen doping influences the the local structure of GeTe, has been published in ACS Applied Materials and Interfaces.
Interestingly when oxygen is added into GeTe, the energy required to switch the material in a phase change random access memory cell is lowered, yet counter intuitively the crystallization temperature is increased by O doping. Previously we showed that there is zero change in density for O concentrations of about 5 at.%. We believe that this allows the material to be switched with a lower enthalpy change, hence explaining the energy efficient memory switching.
The paper is available here: http://pubs.acs.org/doi/abs/10.1021/acsami.6b05071
Our paper on the design of strain engineered chalcogenide superlattices has been published in Nature Communications. The paper presents the design rules for creating superlattices with switchable properties.