Ultrascalability and electron transport properties of ultra-thin film phase change material Ge2Sb2Te5 Ali Roohforouz and Aliasghar Shokri Eur. Phys. J. B, 92 12 (2019) 279 Published online: 25 December 2019 DOI: 10.1140/epjb/e2019-100353-1