Fig. 1: Schematic diagram of the OFZ growth strategy and associated Raman data for the as-grown Lu:HZO bulk crystals.
From: Atomic-scale mechanism unlocks thermal-stable high-κ performance in HfO2 via coherent interfaces
a Free energy distributions of t, o-AFE and o-FE phases. ΔEt/o-AFE and ΔEt/o-FE denote the energy barriers of the phase transitions from t to o-AFE and o-FE phases, respectively6,35,63. The cyan and orange vertical arrows represent the polarization directions. b MPB schematic diagram between the t and o-AFE phases63. The yellow region represents the connected interface. c Designed growth strategy for stabilizing t/o-AFE MPBs to room temperature. The as-grown crystal (cyan shaded frame inside the figure) is moved along the growth direction. T denotes temperature, and TC corresponds to the Curie temperature. The blue curves represent the temperature distribution along the growth direction. The cyan region denotes the t-phase, while the gray spheres correspond to the formed o-AFE phase. d Photograph and room-temperature position-dependent Raman spectra of the as-grown Lu:HZO bulk crystals with different d values corresponding to the d = 0 mm, 5 mm, and d = 10 mm, respectively. (d represents the distance from the uppermost position of the as-grown crystal to the highest heating temperature point (Supplementary Fig. 1)). The theoretical Raman vibrational modes of the t, o-AFE, and o-FE phases are from Ref. 41.
