Temperature-driven transition from the Wigner crystal to the bond-charge-density wave in the quasi-one-dimensional quarter-filled band

Clay, R. Torsten; Hardikar, Rahul; Mazumdar, S.

doi:10.1103/physrevb.76.205118

Cited by 29 publications

(49 citation statements)

References 77 publications

(334 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This state is the simplest realization of the PEC and may visualized as a second dimerization of dimer units of molecules; the singlet bond giving the spin gap (SG) forms between adjacent dimer units. The intermediate temperature bond-dimerized states, WC state, and PEC state with SG are all found experimentally in quasi-1D CTS 58 . Zigzag ladder systems, coupled two-stack systems in which each site on one stack is coupled to two sites on the other stack, are a second realization of the PEC state.…”

mentioning

confidence: 93%

“…Provided the n.n. Coulomb interaction is not too strong, a SP transition occurs from either insulating state 58 , resulting in a ground state with period-4 CO · · · 0110· · · . This state is the simplest realization of the PEC and may visualized as a second dimerization of dimer units of molecules; the singlet bond giving the spin gap (SG) forms between adjacent dimer units.…”

mentioning

confidence: 99%

“…A key difference from the SP transition in ρ = 1 is that for ρ = 1 2 , a MI transition first occurs at a intermediate temperature, followed by the SP transition at low temperature. For ρ = 1 2 , the MI leads to either a bond-dimerized or to a charge-ordered WC state with equal bond lengths 58 . Provided the n.n.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Paired electron crystal: Order from frustration in the quarter-filled band

et al. 2011

Self Cite

View full text Add to dashboard Cite

We present a study of the effects of simultaneous charge-and spin-frustration on the twodimensional strongly correlated quarter-filled band on an anisotropic triangular lattice. Our conclusions are based on exact diagonalization studies that include electron-electron interactions as well as adiabatic electron-phonon coupling terms treated self-consistently. The broken-symmetry states that dominate in the weakly frustrated region near the rectangular lattice limit are the well known antiferromagnetic state with in-phase lattice dimerization along one direction, and the Wigner crystal state with the checkerboard charge order. For moderate to strong frustration, however, the dominant phase is a novel spin-singlet paired-electron crystal (PEC), consisting of pairs of charge-rich sites separated by pairs of charge-poor sites. The PEC, with coexisting charge-order and spin-gap in two dimension, is the quarter-filled band equivalent of the valence bond solid (VBS) that can appear in the frustrated half-filled band within antiferromagnetic spin Hamiltonians. We discuss the phase diagram as a function of on-site and intersite Coulomb interactions as well as electronphonon coupling strength. We speculate that the spin-bonded pairs of the PEC can become mobile for even stronger frustration, giving rise to a paired-electron liquid. We discuss the implications of the PEC concept for understanding several classes of quarter-filled band materials that display unconventional superconductivity, focusing in particular on organic charge transfer solids. Our work points out the need to go beyond quantum spin liquid (QSL) concepts for highly frustrated organic charge-transfer solids such as κ-(BEDT-TTF)2Cu2(CN)3 and EtMe3Sb[Pd(dmit)2]2, which we believe show frustration-induced charge disproportionation at low temperatures. We discuss possible application to layered cobaltates and 1 4 -filled band spinels.

show abstract

mentioning

confidence: 93%

mentioning

confidence: 99%

See 1 more Smart Citation

Paired electron crystal: Order from frustration in the quarter-filled band

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…[11][12][13][14][15][16] In such studies, it is crucial to treat 1D electronic fluctuations properly, which originate from the strong electron correlation. This is because development of correlation lengths is strongly anisotropic along 1D chains, which finally results in phase transitions through interchain interaction or coupling to the three-dimensional lattice.…”

mentioning

confidence: 99%

Finite-Temperature Phase Diagram of Quasi-One-Dimensional Molecular Conductors: Quantum Monte Carlo Study

et al. 2008

View full text Add to dashboard Cite

Finite-temperature phase transitions in quasi-one-dimensional quarter-filled systems are investigated using the extended Hubbard model with electron-lattice coupling. By a quantum Monte Carlo method combined with interchain mean-field approximation, we clarify competing and coexisting behaviors among charge ordering, dimer Mott, and spin-Peierls states. It is pointed out that an anharmonicity of lattice distortions plays an important role in multicritical behaviors. The results are compared with experimental data for quasi-one-dimensional molecular conductors such as DCNQI and TMTTF compounds.KEYWORDS: quasi-one-dimensional molecular conductors, extended Hubbard model, electron-lattice coupling, charge ordering, lattice dimerization, spin-Peierls transition, SSE Monte Carlo methodQuasi-one-dimensional (Q1D) molecular conductors have been recognized as materials suitable for studying the effects of strong correlation. In these compounds, Coulomb interaction and enhanced fluctuations due to low dimensionality give rise to keen competitions in charge, spin, and lattice degrees of freedoms. As a result, they show various phase transitions despite the fact that their noninteracting band structures are often very similar. 1A typical case is the family of (R 1 R 2 -DCNQI) 2 X (R 1 , R 2 : substituents, X: monovalent cation). The electronic structure is commonly described by a Q1D quarter-filled π-band of DCNQI chains, 2 whereas their physical properties depend strongly on R 1 , R 2 , and X. For instance, DI-DCNQI 2 Ag shows a charge-ordering (CO) phase transition at T = 220 K and an antiferromagnetic transition at 5 K.3, 4 On the other hand, DMe-DCNQI 2 Ag exhibits, instead of CO, lattice dimerization at T = 100 K, which drives the system effectively half-filled, resulting in a dimer Mott (DM) insulating state. Furthermore, tetramerization occurs at T = 80 K, which is ascribed to a spin-Peierls (SP) transition.5 Such a variety of properties suggests a subtle balance among different phases under electron correlation.Another good example is found in (TMTTF) 2 X (X: monovalent anion), whose Q1D π-band of TMTTF chains is quarter-filled in terms of holes.6 In contrast to the DCNQI systems, an intrinsic dimerization exists along the chains from the outset. These compounds also exhibit rich phases depending on X. The CO transition occurs at around 100 K, which is followed by a SP transition at a lower temperature (T ) for X = PF 6 and AsF 6 or an antiferromagnetic transition for X= SbF 6 . 7-9 For X = AsF 6 , the CO phase is suppressed under applied pressure (P ), while the SP state persists up to higher P . This indicates that the CO and SP states are competing in nature.8 * E-mail: otsuka@sci.u-hyogo.ac.jp Theoretically, correlation effects in such Q1D molecular conductors have been studied using the 1D or Q1D quarter-filled extended Hubbard model with on-site and intersite Coulomb interactions, mainly focusing on the ground state.10 Several studies have recently been conducted to describe their finite-T properties. [11][12...

show abstract

“…Numerical methods are powerful in investigating and have been applied to reveal the finite-T properties of such models [36][37][38]. This is in contrast and complementary to the analytical approaches which provide insights to the phenomena, for example, described by means of the TLL parameters in the bosonization scheme.…”

Section: Numerical Studymentioning

confidence: 99%

Theoretical Studies on Phase Transitions in Quasi-One-Dimensional Molecular Conductors

2012

View full text Add to dashboard Cite

A review is given for recent theoretical studies on phase transitions in quasi-one-dimensional molecular conductors with a quarter-filled band. By lowering temperature, charge transfer salts exhibit a variety of transitions accompanying symmetry breaking, such as charge ordering, lattice dimerization, antiferromagnetic transition, spin-Peierls distortion, and so on. Analyses on microscopic quasi-one-dimensional models provide their systematic understandings, by the complementary use of different analytical and numerical techniques; they can reproduce finite-temperature phase transitions, whose results can be directly compared with experiments and give feedbacks to material design.

show abstract

Temperature-driven transition from the Wigner crystal to the bond-charge-density wave in the quasi-one-dimensional quarter-filled band

Cited by 29 publications

References 77 publications

Paired electron crystal: Order from frustration in the quarter-filled band

Paired electron crystal: Order from frustration in the quarter-filled band

Finite-Temperature Phase Diagram of Quasi-One-Dimensional Molecular Conductors: Quantum Monte Carlo Study

Theoretical Studies on Phase Transitions in Quasi-One-Dimensional Molecular Conductors

Contact Info

Product

Resources

About