Tungsten-doped Ge2Sb2Te5 phase change material for high-speed optical switching devices. - Guo, Pengfei; Burrow, Joshua A.; Sevison, Gary A.; Kwon, Heungdong; Perez, Christopher; Hendrickson, Joshua R.; Smith, Evan M.; Asheghi, Mehdi; Goodson, Kenneth E.; Agha, Imad; Sarangan, Andrew M. (Applied Physics Letters, 2020)