scholarly journals Hidden Charge Orders in Low-Dimensional Mott Insulators

2019 ◽  
Vol 9 (4) ◽  
pp. 784
Author(s):  
Serena Fazzini ◽  
Arianna Montorsi
Keyword(s):  
Hubbard Model ◽  
Density Wave ◽  
Finite Size ◽  
Charge Order ◽  
Mott Insulators ◽  
Coulomb Interactions ◽  
Non Local ◽  
Low Dimensional ◽  
A Charge ◽  
Insulating Phase

The opening of a charge gap driven by interaction is a fingerprint of the transition to a Mott insulating phase. In strongly correlated low-dimensional quantum systems, it can be associated to the ordering of hidden non-local operators. For Fermionic 1D models, in the presence of spin–charge separation and short-ranged interaction, a bosonization analysis proves that such operators are the parity and/or string charge operators. In fact, a finite fractional non-local parity charge order is also capable of characterizing some two-dimensional Mott insulators, in both the Fermionic and the bosonic cases. When string charge order takes place in 1D, degenerate edge modes with fractional charge appear, peculiar of a topological insulator. In this article, we review the above framework, and we test it to investigate through density-matrix-renormalization-group (DMRG) numerical analysis the robustness of both hidden orders at half-filling in the 1D Fermionic Hubbard model extended with long range density-density interaction. The preliminary results obtained at finite size including several neighbors in the case of dipolar, screened and unscreened repulsive Coulomb interactions, confirm the phase diagram of the standard extended Hubbard model. Besides the trivial Mott phase, the bond ordered and charge density wave insulating phases are also not destroyed by longer ranged interaction, and still manifest hidden non-local orders.

scholarly journals NOVEL PHENOMENA IN CHARGED BOSE LIQUID

1998 ◽  
Vol 13 (12) ◽  
pp. 987-994 ◽  
Author(s):  
KIMYEONG LEE ◽  
OLEG TCHERNYSHYOV
Keyword(s):  
Charge Density ◽  
Density Wave ◽  
Finite Size ◽  
Charge Density Waves ◽  
Two Dimensions ◽  
Coulomb Interactions ◽  
Density Waves ◽  
Boson Exchange ◽  
Bose Liquid ◽  
Uniform Background

We investigate charged Bose liquid immersed in uniform background charge at zero temperature. Novel phenomena, such as oscillatory shielding of external localized electric charge, rotons and charge density waves (charge stripes in two dimensions), occur in any dimensions. Oscillatory shielding is caused by mixing between scalar boson exchange and Coulomb interactions, which mediate opposite forces. On the other hand, rotons and charge density waves are due to attractive local self-interaction of bosons. Rotons can be regarded as a finite size charge density wave packet without any back flow. We also comment on charge stripes observed recently in cuprates and nickelates.

scholarly journals Природа псевдощелевой фазы ВТСП купратов

2020 ◽  
Vol 62 (9) ◽  
pp. 1390
Author(s):  
А.С. Москвин ◽  
Ю.Д. Панов
Keyword(s):  
Density Wave ◽  
Charge Order ◽  
Lattice Relaxation ◽  
Field Approximation ◽  
Cuo2 Plane ◽  
Local Order ◽  
Effective Spin ◽  
Quantum Electron ◽  
A Charge ◽  
Quantum Antiferromagnet

The pseudogap phase of HTSC cuprates is associated with the formation of a system of quantum electron-hole (EH) dimers similar to the Anderson RVB-phase. We considered the specific role of electron-lattice relaxation in the formation of metastable EH dimers in cuprates with T- and T′-structures. In the model of charge triplets and S = 1 pseudospin formalism, the effective spin-pseudospin Hamiltonian of the cuprate CuO2 plane is introduced. In the framework of the molecular field approximation (MFA) for the coordinate representation, the main MFA phases were found: an antiferromagnetic insulator, a charge density wave, a bosonic superconductor with d-symmetry of the order parameter, and two metal Fermi-phases forming the phase of the "strange" metal. We argue that the MFA can correctly reproduce all the features of the typical cuprate phase diagrams. As for typical s = 1/2 quantum antiferromagnet the actually observed cuprate phases such as charge order and superconductivity reflect "physical" ground state, which is close to MFA-phases but with strongly reduced magnitudes of the local order parameters.

Charge density wave formation in the low-temperature-tetragonal phase of cuprates

2002 ◽  
Vol 12 (9) ◽  
pp. 251-251
Author(s):  
C. Morais Smith ◽  
N. Hasselmann ◽  
A. H. Castro Neto
Keyword(s):  
Low Temperature ◽  
Charge Density ◽  
Tetragonal Phase ◽  
Charge Density Wave ◽  
Density Wave ◽  
Charge Order ◽  
High Tc ◽  
A Charge ◽  
High Tc Cuprates ◽  
Shed Light

We calculate the influence of transverse fluctuations on the longitudinal dynamics in the striped phase of cuprates by using the bosonization technique. We find that a charge density wave instability can arise if the stripe is quarter filled and the underlying lattice potential has a zig-zag symmetry. Our results shed light on the as yet not understood connection between the formation of a low temperature tetragonal phase and the subsequent appearance of charge order in high-Tc cuprates.

THE COULOMB FORCE AND THE VARIOUS THERMODYNAMIC PHASES OF SIMPLE METALS

1990 ◽  
Vol 04 (01) ◽  
pp. 1-43 ◽  
Author(s):  
DANIEL C. MATTIS
Keyword(s):  
High Temperature Superconductivity ◽  
Density Wave ◽  
Coulomb Repulsion ◽  
Coulomb Force ◽  
Companion Paper ◽  
Coulomb Interactions ◽  
Solid State Physics ◽  
Hubbard Interaction ◽  
Charge Density Wave Phase ◽  
A Charge

With just two-body Coulomb interactions between electrons being taken into account, the phase diagram of a simple metal includes the following phases at least: the ordinary paramagnetic Fermi liquid, itinerant ferromagnetism, a charge-density wave phase and an antiferromagnetic phase (either of which can be insulating), and — surprisingly — a superconducting phase. The present work surveys the physics of the Coulomb interactions in metals, and the diverse roles played by the zero-range Hubbard interaction U0 and the long-range Coulomb interactions denoted ΔV (q). Screening of the latter by the currents in the metal is treated in some detail. This work is intended as an introduction into an important area of solid-state physics. A number of novel ideas are proposed, but are clearly identified as such. For example: although V (q) ≡ U0 + ∆V (q) is required to be positive at all q, υ(q) ≡ (1/2) U0 + ∆V (q) is not. We show that if υ (q) < 0 in a given phase, that phase is unstable (regardless of band structure, etc.). We also find that the Coulomb repulsion between electrons in a given band is somewhat stronger than that between holes. A companion paper based on the concepts presented here elaborates the theory of high-temperature superconductivity in layered metals.

THEORY OF CRITICAL CHARGE FLUCTUATIONS AND PSEUDOGAP FORMATION IN THE SINGLE-BAND HUBBARD MODEL

2000 ◽  
Vol 14 (25n27) ◽  
pp. 3000-3005 ◽  
Author(s):  
ROBERTA CITRO ◽  
MARIO MARINARO
Keyword(s):  
Hubbard Model ◽  
Density Wave ◽  
Charge Ordering ◽  
Single Band ◽  
Electron Interaction ◽  
Charge Fluctuations ◽  
Effective Electron ◽  
Critical Charge ◽  
A Charge ◽  
Precursor Effects

Within a single-band Hubbard model, treated by means of a strong-coupling approach based on a cumulant expansion, we investigate the existence of critical charge fluctuations (CCF) that could give rise to a phase separation (PS) or a charge density wave, by means of a Bethe-Salpeter equation for the vertex function in the particle-hole channel. We discuss the relevance of the precursor effects of charge ordering on the self-energy of the electrons and the non-Fermi liquid behavior arising from an effective electron-electron interaction.

scholarly journals Tri-Hexagonal charge order in kagome metal CsV3Sb5 revealed by 121Sb NQR

2021 ◽  
Author(s):  
Chao Mu ◽  
Qiangwei Yin ◽  
Zhijun Tu ◽  
Chunsheng Gong ◽  
Ping Zheng ◽  
...  
Keyword(s):  
Density Wave ◽  
Charge Order ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
S Wave ◽  
First Order ◽  
First Order Phase Transition ◽  
Quadrupole Resonance ◽  
A Charge ◽  
First Order Phase

Abstract We report 121Sb nuclear quadrupole resonance (NQR) measurements on kagome superconductor CsV3Sb5 with T c = 2.5 K. 121Sb NQR spectra split after a charge density wave (CDW) transition at 94 K, which demonstrates a commensurate CDW state. The coexistence of the high temperature phase and the CDW phase between 91 K and 94 K manifests that it is a first order phase transition. The CDW order exhibits Tri-Hexagonal deformation with a lateral shift between the adjacent kagome layers, which is consistent with 2×2×2 superlattice modulation. The superconducting state coexists with CDW order and shows a conventional s-wave behavior in the bulk state.

scholarly journals Charge-Order Phase Transition in the Quasi One-Dimensional Organic Conductor $${\hbox {(TMTTF)}}_2 {\hbox {NO}}_3$$

2020 ◽  
Vol 51 (11) ◽  
pp. 1321-1329
Author(s):  
Lena Nadine Majer ◽  
Björn Miksch ◽  
Guilherme Gorgen Lesseux ◽  
Gabriele Untereiner ◽  
Martin Dressel
Keyword(s):  
Charge Order ◽  
Relaxation Processes ◽  
Organic Conductor ◽  
One Dimensional ◽  
Spin Resonance ◽  
Ordered Phases ◽  
Spin Arrangement ◽  
Low Dimensional ◽  
A Charge ◽  
Pm 10

AbstractLow-dimensional organic conductors show a rich phase diagram, which has, despite all efforts, still some unexplored regions. Charge ordered phases present in many compounds of the $${\hbox {(TMTTF)}}_2X$$ (TMTTF) 2 X family are typically studied with their unique electronic properties in mind. An influence on the spin arrangement is, however, not expected at first glance. Here, we report temperature and angle dependent electron spin resonance (ESR) measurements on the quasi one-dimensional organic conductor $${\hbox {(TMTTF)}}_2 {\hbox {NO}}_3$$ (TMTTF) 2 NO 3 . We found that the $${\hbox {(TMTTF)}}_2 {\hbox {NO}}_3$$ (TMTTF) 2 NO 3 compound develops a peculiar anisotropy with a doubled periodicity ($$ab'$$ a b ′ -plane) of the ESR linewidth below about $$T_{\text {CO}}= ({250\pm 10})~\hbox {K}$$ T CO = ( 250 ± 10 ) K . This behavior is similar to observations in the related compounds $${\hbox {(TMTTF)}}_2X$$ (TMTTF) 2 X ($$X = {\hbox {PF}}_6$$ X = PF 6 , $${\hbox {SbF}}_6$$ SbF 6 and $${\hbox {AsF}}_6$$ AsF 6 ), where it has been attributed to relaxation processes of magnetically inequivalent sites in the charge-ordered state. For the structural analogous $${\hbox {(TMTTF)}}_2 {\hbox {ClO}}_4$$ (TMTTF) 2 ClO 4 , known for the absence of charge order, such angular dependence of the ESR signal is not observed. Therefore, our ESR measurements lead us to conclude that a charge-order phase is stabilized in the title compound below $$T_{\text {CO}} \approx 250~\hbox {K}$$ T CO ≈ 250 K .

scholarly journals Ultrafast formation of domain walls of a charge density wave in SmTe3

2021 ◽  
Vol 103 (5) ◽  
Author(s):  
M. Trigo ◽  
P. Giraldo-Gallo ◽  
J. N. Clark ◽  
M. E. Kozina ◽  
T. Henighan ◽  
...  
Keyword(s):  
Charge Density ◽  
Charge Density Wave ◽  
Domain Walls ◽  
Density Wave ◽  
A Charge
Sign in / Sign up

Export Citation Format

Share Document