%0 Journal Article %1 liu2017stable %A Liu, Shi %A Cohen, RE %D 2017 %I IOP Publishing %J Journal of Physics: Condensed Matter %K charged_domain_walls domain_walls ferroelectric_photovoltaics theory %N 24 %P 244003 %T Stable charged antiparallel domain walls in hyperferroelectrics %V 29 %X Charge-neutral 180° domain walls that separate domains of antiparallel polarization directions are common structural topological defects in ferroelectrics. In normal ferroelectrics, charged 180° domain walls running perpendicular to the polarization directions are highly energetically unfavorable because of the depolarization field and are difficult to stabilize. We explore both neutral and charged 180° domain walls in hyperferroelectrics, a class of proper ferroelectrics with persistent polarization in the presence of a depolarization field, using density functional theory. We obtain zero temperature equilibrium structures of head-to-head and tail-to-tail walls in recently discovered ABC-type hexagonal hyperferroelectrics. Charged domain walls can also be stabilized in canonical ferroelectrics represented by LiNbO3 without any dopants, defects or mechanical clamping. First-principles electronic structure calculations show that charged domain walls can reduce and even close the band gap of host materials and support quasi-two-dimensional electron(hole) gas with enhanced electrical conductivity.

@article{liu2017stable, abstract = {Charge-neutral 180° domain walls that separate domains of antiparallel polarization directions are common structural topological defects in ferroelectrics. In normal ferroelectrics, charged 180° domain walls running perpendicular to the polarization directions are highly energetically unfavorable because of the depolarization field and are difficult to stabilize. We explore both neutral and charged 180° domain walls in hyperferroelectrics, a class of proper ferroelectrics with persistent polarization in the presence of a depolarization field, using density functional theory. We obtain zero temperature equilibrium structures of head-to-head and tail-to-tail walls in recently discovered ABC-type hexagonal hyperferroelectrics. Charged domain walls can also be stabilized in canonical ferroelectrics represented by LiNbO3 without any dopants, defects or mechanical clamping. First-principles electronic structure calculations show that charged domain walls can reduce and even close the band gap of host materials and support quasi-two-dimensional electron(hole) gas with enhanced electrical conductivity.}, added-at = {2018-08-19T23:34:45.000+0200}, author = {Liu, Shi and Cohen, RE}, biburl = {https://www.bibsonomy.org/bibtex/2983c8a627d5cee3fbd8fb34844be3f1e/skoerbel}, interhash = {7ed8dd3b6508f914b06f9db5e5473b72}, intrahash = {983c8a627d5cee3fbd8fb34844be3f1e}, journal = {Journal of Physics: Condensed Matter}, keywords = {charged_domain_walls domain_walls ferroelectric_photovoltaics theory}, number = 24, pages = 244003, publisher = {IOP Publishing}, timestamp = {2018-08-20T00:12:10.000+0200}, title = {Stable charged antiparallel domain walls in hyperferroelectrics}, volume = 29, year = 2017 }