An orbital ordering transition and electronic phase coexistence have been discovered in SrCrO3. This cubic, orbitally-degenerate perovskite transforms to a tetragonal phase with partial orbital order. The tetragonal phase is antiferromagnetic below 35-40 K, whereas the cubic phase remains paramagnetic at low temperatures. The orbital ordering temperature (35-70 K) and coexistence of the two electronic phases are very sensitive to lattice strain. X-ray measurements show a preferential conversion of the most strained regions in the cubic phase. This reveals that small fluctuations in microstrain are sufficient to drive long range separation of competing electronic phases even in undoped cubic oxides.

High-pressure is utilized to realize new 2D layered structures in PdSe2 with high-mobility transport anisotropy for photovoltaic applications.

General rightsCopyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other copyright owners and it is a condition of accessing these publications that users recognise and abide by the legal requirements associated with these rights. Take down policyThe University of Edinburgh has made every reasonable effort to ensure that Edinburgh Research Explorer content complies with UK legislation. If you believe that the public display of this file breaches copyright please contact openaccess@ed.ac.uk providing details, and we will remove access to the work immediately and investigate your claim. A full range of SrRu 1−x Cr x O 3 perovskite solid solutions ͑0 Ͻ x Ͻ 1͒ has been prepared using high temperatures and pressures up to 10.5 GPa. The structure changes from orthorhombic Pbnm at low x through a previously unreported rhombohedral R3c phase at x = 0.4 to cubic Pm3m for 0.5Ͻ x Ͻ 1. No Cr/ Ru order is evidenced at any x. A substantial Ru 4+ +Cr 4+ → Ru 5+ +Cr 3+ charge transfer is evidenced by a volume discontinuity close to x = 0.5. Low Cr-doped materials ͑x Ͻ 0.3͒ are itinerant, and ferromagnetic below 160-190 K, and x Ͼ 0.7 materials are itinerant and Pauli paramagnetic, but a substantial insulating region is found between these limits. Neutron diffraction shows the x = 0.4 material to be antiferromagnetic with a high Néel temperature ϳ400 K and a saturated moment of 1.7 B , despite the large Cr/ Ru disorder. A 50 K magnetic transition and a low temperature structural phase change to orthorhombic Imma symmetry have been discovered in SrCrO 3 , suggesting that the ground state of this simple perovskite is more complex than was previously assumed.