Strain engineering and one-dimensional organization of metal-insulator domains in single-crystal VO2 beams

Spatial phase inhomogeneity at the nano- to microscale is widely observed in strongly-correlated electron materials. The underlying mechanism and possibility of artificially controlling the phase inhomogeneity are still open questions of critical importance for both the phase transition physics and device applications. Lattice strain has been shown to cause the coexistence of metallic and insulating phases in the Mott insulator VO2. By continuously tuning strain over a wide range in single-crystal VO2 micro- and nanobeams, here we demonstrate the nucleation and manipulation of one-dimensionally ordered metal-insulator domain arrays along the beams. Mott transition is achieved in these beams at room temperature by active control of strain. The ability to engineer phase inhomogeneity with strain lends insight into correlated electron materials in general, and opens opportunities for designing and controlling the phase inhomogeneity of correlated electron materials for micro- and nanoscale device applications.Comment: 14 pages, 4 figures, with supplementary informatio

Martensitic transformations in constrained films

The evolution of martensitic microstructure and stress in a constrained film coupled with a substrate under cooling and heating is considered. Thermodynamic analysis has done using the special phase diagrams constructed in coordinates temperature-film/ substrate misfit

Demonstration of ultra-high recyclable energy densities in domain-engineered ferroelectric films

Dielectric capacitors offer high-power delivery materials for energy-storage, yet suffer from low energy densities. Here, the authors prepared ferroelectric Ba(Zr0.2,Ti0.8)O3 that utilizes polydomain nanostructures to delay electric polarization saturation and boost energy densities