Talk at SIOM, Shanghai, China

R. E. Simpson will give a talk at the Shanghai Institute of Optics and Fine Mechanics on 24th June 2015.

Phase change materials: structure, design, and applications in photonics

The crystallisation kinetics, electrical properties, and the refractive index of the well known GeTe-Sb2Te3 phase change data storage materials are commonly tuned by adjusting the composition or alloying with other elements. However, the effect of strain has not been exploited as a means to design the properties of phase change materials, yet in microelectronics material research, ‘strain engineering’ is the principal technique used to enhance the performance of metal oxide semiconductor field-effect transistors (MOSFETs). In this presentation I will describe how strain can be used to tune phase change materials and phase change superlattice structures. The talk will include our latest results from experiment and simulation whilst also projecting forward to discuss the application of phase change materials to photonics.

Talk at Dalian University of Technology, China

R. E. Simpson will give a talk at the Dalian University of Technology on 22/23rd June 2015.

Phase change materials: structure, design, and applications in photonics

The crystallisation kinetics, electrical properties, and the refractive index of the well known GeTe-Sb2Te3 phase change data storage materials are commonly tuned by adjusting the composition or alloying with other elements. However, the effect of strain has not been exploited as a means to design the properties of phase change materials, yet in microelectronics material research, ‘strain engineering’ is the principal technique used to enhance the performance of metal oxide semiconductor field-effect transistors (MOSFETs). In this presentation I will describe how strain can be used to tune phase change materials and phase change superlattice structures. The talk will include our latest results from experiment and simulation whilst also projecting forward to discuss the application of phase change materials to photonics.

Jitendra Behera to present at MRS

Jitendra Behera will be presenting at the 2015 Materials Research Society meeting in San Francisco. His talk will discuss non-phase change electrical switching in Ge2Sb2Te5 memory cells.

Interfacial Phase Change Memory Paper awarded prestigious best paper award

Authors of Interfacial Phase Change Memory
Authors of Interfacial Phase Change Memory

R.E. Simpson (ACTA Lab Principle Investigator), P Fons, A. V. Kolobov, T. Fukaya, M. Krbal, T. Yagi, and J. Tominaga were awarded the the best paper prize for their Nature Nanotechnology article: R. E. Simpson, P. Fons, A. V. Kolobov, T. Fukaya, M. Krbal, T. Yagi, and J. Tominaga Nat. Nano. 6(8) 501-505 (2011).

The prize was awarded by the Japanese Institute for Advanced Industrial Science and Technology (AIST) chairmen on the 5th November 2014. AIST usually presents the best paper award two or three years after paper publication such that the paper’s impact can be properly measured. The AIST chairpeople recognised that the paper has stimulated new domestic and international research projects leading to a new field in nano structured phase change materials.

The paper was published in 2011 and describes how the interface between two different phase change materials, GeTe and Sb2Te3, can be designed and engineered to create improved phase change memory behaviour. The special phase change superlattice structure is known as an Interfacial Phase Change Material (iPCM). A followup paper, which was published in 2012 and highlighted in Nature Nanotechnology, goes further to describe how switching in iPCM memory devices is influenced by a magnetic field and this strongly indicates the existence of a topologically non-trivial band-structure.

The iPCM project was R. E Simpson’s postdoctoral project from 2008 until 2011. Prof Tominaga of AIST was the principle investigator for the iPCM project. Prof Tominaga accepted the award at a ceremony held in Tsukuba, Japan, on the 5th of November 2014.

Prof Tominaga’s presentation (in Japanese) at the awards ceremony can viewed below:

Further details (in Japanese) can also be found here and here.