Optical creation of a supercrystal with three-dimensional nanoscale periodicity

Journal Article

Stoica, V.A, N Laanait, C Dai, Z Hong, Y Yuan, Z Zhang, S Lei, M.R McCarter, Ajay K Yadav, A.R Damodaran, S Das, G.A Stone, J Karapetrova, D.A Walko, X Zhang, L.W Martin, Ramamoorthy Ramesh, L.-Q Chen, H Wen, V Gopalan, J.W Freeland

10.1038/s41563-019-0311-x

Stimulation with ultrafast light pulses can realize and manipulate states of matter with emergent structural, electronic and magnetic phenomena. However, these non-equilibrium phases are often transient and the challenge is to stabilize them as persistent states. Here, we show that atomic-scale PbTiO 3 /SrTiO 3 superlattices, counterpoising strain and polarization states in alternate layers, are converted by sub-picosecond optical pulses to a supercrystal phase. This phase persists indefinitely under ambient conditions, has not been created via equilibrium routes, and can be erased by heating. X-ray scattering and microscopy show this unusual phase consists of a coherent three-dimensional structure with polar, strain and charge-ordering periodicities of up to 30 nm. By adjusting only dielectric properties, the phase-field model describes this emergent phase as a photo-induced charge-stabilized supercrystal formed from a two-phase equilibrium state. Our results demonstrate opportunities for light-activated pathways to thermally inaccessible and emergent metastable states. © 2019, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.

Nature Materials

18

2019

14761122

cited By 9

Ramesh Lab