title: Presence of Peierls pairing and absence of insulator-to-metal transition in VO2(A): a structure-property relationship study.
abstract: Layered vanadium oxides have been extensively explored due to their interesting metal-insulator transitions and energy conversion/storage applications. In the present study, we have successfully synthesized VO2(A) polymorph powder samples by a single-step hydrothermal synthesis process and consolidated them using spark plasma sintering. The structural and electronic properties of VO2(A) are measured over a large temperature range from liquid helium, across the structural transition (400-440 K) and up to 500 K. The structural analysis around this transition reveals an antiferrodistorsive to partially ferrodistorsive ordering upon cooling. It is followed by a progressive antiferromagnetic spin pairing which fully settles at about 150 K. The transport measurements show that, in contrast to the rutile archetype VO2(R/M1), the structural transition comes with a transition from semiconductor to band-type insulator. Under these circumstances, we propose a scenario with a high temperature antiferrodistorsive paramagnetic semiconducting phase, followed by an intermediate regime with a partially ferrodistorsive paramagnetic semiconducting phase, and finally a low temperature partially ferrodistorsive antiferromagnetic band insulator phase with a possible V-V Peierls-type pairing.
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Michael.Pollet@icmcb.cnrs.fr and Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France and INCEMC, Plautius Andronescu 1, 300224, Timisoara, Romania.
authors.forename: S R
authors.identifier: http://orcid.org/0000-0001-5990-1864
authors.initials: SR
authors.lastname: Popuri
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Michael.Pollet@icmcb.cnrs.fr and Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors.forename: A
authors.initials: A
authors.lastname: Artemenko
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Michael.Pollet@icmcb.cnrs.fr and Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors.forename: R
authors.initials: R
authors.lastname: Decourt
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Michael.Pollet@icmcb.cnrs.fr and Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors.forename: A
authors.initials: A
authors.lastname: Villesuzanne
authors.affiliation: CNRS, ICMCB, UPR 9048, F-33600 Pessac, France. Michael.Pollet@icmcb.cnrs.fr and Univ. Bordeaux, ICMCB, UPR 9048, F-33600 Pessac, France.
authors.forename: M
authors.initials: M
authors.lastname: Pollet