Charge-ordering phenomena have been highly topical over the past few years. A phase transition towards a charge-ordered state has been observed experimentally in several classes of materials. Among them, many studies have been devoted to the family of quasi-one-dimensional organic charge-transfer salts (TMTTF)2X, where (TMTTF) stands for tetramethyltetrathiafulvalene and X for a monovalent anion (X = PF6, AsF6 and SbF6). However, the relationship between the electron localization phenomena and the role of the lattice distortion in stabilizing the charge-ordering pattern is poorly documented in the literature. Here we present a brief overview of selected literature results, with emphasis placed on recent thermal expansion experiments probing the charge-ordering transition of these salts.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1088/0953-8984/25/34/343201 | DOI Listing |
RSC Adv
November 2024
Department of Physics, Shri Madhavrao Patil Mahavidyalaya Murum, Tq. Omerga Osmanabad-413606 M.S. India
Nanocomposites of 20% and 30% Co-doped Ni/NiO were synthesized using a microwave-assisted sol-gel auto-combustion method. The 30% Co-doped Ni/NiO nanocomposite exhibited negative magnetoresistance (M-R) at various temperatures, including 2 K, 10 K, 80 K, 100 K, and 250 K. This behavior is interpreted as indicative of a Kondo-like scattering effect.
View Article and Find Full Text PDFPhys Rev Lett
October 2024
Theoretical Materials Physics, Q-MAT, Université de Liège, B-4000 Sart-Tilman, Belgium.
BiNiO_{3} exhibits an unusual metal-insulator transition from Pnma to P1[over ¯] that is related to charge ordering at the Bi sites, which is intriguingly distinct from the charge ordering at Ni sites usually observed in related rare-earth nickelates. Here, using first principles calculations, we first rationalize the phase transition from Pnma to P1[over ¯], revealing an overlooked intermediate P2_{1}/m bridging phase and a complex interplay between distinct degrees of freedom. Going further, we point out that the charge ordering at Bi sites in the P1[over ¯] phase is not unique.
View Article and Find Full Text PDFNat Chem
October 2024
Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany.
Layered perovskites with Ruddlesden-Popper-type structures are fundamentally important for low-dimensional properties, for example, photovoltaic hybrid iodides and superconducting copper oxides. Many such halides and oxides are known, but analogous nitrides are difficult to stabilize due to the high cation oxidation states required to balance the anion charges. Here we report the high-pressure synthesis of three single-layer Ruddlesden-Popper (KNiF type) nitrides-PrReN, NdReN and CeTaN-along with their structural characterization and properties.
View Article and Find Full Text PDFNature
June 2024
Key Laboratory for Quantum Materials of Zhejiang Province, Department of Physics, School of Science and Research Center for Industries of the Future, Westlake University, Hangzhou, People's Republic of China.
The interplay among frustrated lattice geometry, non-trivial band topology and correlation yields rich quantum states of matter in kagome systems. A series of recent members in this family, AVSb (A = K, Rb or Cs), exhibit a cascade of symmetry-breaking transitions, involving the 3Q chiral charge ordering, electronic nematicity, roton pair density wave and superconductivity. The nature of the superconducting order is yet to be resolved.
View Article and Find Full Text PDFACS Mater Au
May 2024
School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India.
Strong correlations are often manifested by exotic electronic phases and phase transitions. LaCoO (LCO) is a system that exhibits such strong electronic correlations with lattice-spin-charge-orbital degrees of freedom. Here, we show that mesoscopic oxygen-deficient LCO films show resistive avalanches of about 2 orders of magnitude due to the metal-insulator transition (MIT) of the film at about 372 K for the 25 W RF power-deposited LCO film on the Si/SiO substrate.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!