Valence Bond Orders at Charge Neutrality in a Possible Two-Orbital Extended Hubbard Model for Twisted Bilayer Graphene.

08:00 EDT 11th October 2019 | BioPortfolio

Summary of "Valence Bond Orders at Charge Neutrality in a Possible Two-Orbital Extended Hubbard Model for Twisted Bilayer Graphene."

An extended Hubbard model on a honeycomb lattice with two orbitals per site at charge neutrality is investigated with unbiased large-scale quantum Monte Carlo simulations. The Fermi velocity of the Dirac fermions is renormalized as the cluster charge interaction increases, until a mass term emerges and a quantum phase transition from Dirac semimetal to valence bond solid (VBS) insulator is established. The quantum critical point is discovered to belong to the 3D N=4 Gross-Neveu chiral XY universality with the critical exponents obtained at high precision. Further enhancement of the interaction drives the system into two different VBS phases, the properties and transition between them are also revealed. Since the model is related to magic-angle twisted bilayer graphene, our results may have relevance towards the symmetry breaking order at the charge neutrality point of the material, and associate the wide range of universal strange metal behavior around it with quantum critical fluctuations.


Journal Details

This article was published in the following journal.

Name: Physical review letters
ISSN: 1079-7114
Pages: 157601


DeepDyve research library

PubMed Articles [6162 Associated PubMed Articles listed on BioPortfolio]

Characterization of Rh-Al Bond in Rh(PAlP) (PAlP = Pincer-type Diphosphino-Aluminyl Ligand) in Comparison with Rh(L)(PMe) (L = AlMe, Al(NMe), BR, SiR, CH, Cl, or OCH): Theoretical Insight.

The unique Rh-Al bond in recently synthesized Rh(PAlP) 1 {PAlP = pincer-type diphosphino-aluminyl ligand Al[NCH(P Pr)](CH)NMe} was investigated using the DFT method. Complex 1 has four doubly occupied...

Valence-to-Core X-ray Emission Spectroscopy as a Probe of O-O Bond Activation in Cu2O2 complexes.

Valence-to-Core (VtC) X-ray emission spectroscopy (XES) was used to directly detect the presence of an O-O bond in a complex comprising the [Cu2(II)(µ-η2:η2-O2)]2+ core relative to its isomer with ...

Electron-pair bonding in real space. Is the charge-shift family supported?

Charge-shift bonding (CSB) has been introduced as a distinct third family of electron-pair links that adds to the covalent and ionic tradition. However, the full battery of orbital invariant tools pro...

Charge-Shift Bonding: A New and Unique Form of Bonding.

Charge-shift bonds (CSB) constitute a new class of bonds different than covalent/polar-covalent and ionic-bonds. Bonding in CSB is not contributed by either the covalent or the ionic structures of the...

π-Radical Formation by Pyrrolic H Abstraction of Phthalocyanine Molecules on Molybdenum Disulfide.

For a molecular radical to be stable, the environment needs to be inert. Furthermore, an unpaired electron is less likely to react chemically, when it is placed in an extended orbital. Here, we use th...

Clinical Trials [1778 Associated Clinical Trials listed on BioPortfolio]

Prospective Multicenter Trial to Compare Preformed vs Non Preformed Orbital Implants

Accuracy of posttraumatic orbital reconstruction of the meidal orbital wall and/or floor is better with preoperatively preformed orbital implants than with non-preformed orbital implants.

The Use of 3D Printing in Orbital Fractures

The study is a prospective randomized longitudinal clinical study to compare pre-adapted patient-specific orbital implants utilizing an office-based 3-D printer versus standard non-adapted...

Study of Automated Care Pathway for Patients With Chronic Obstructive Pulmonary Disease (COPD)

This is a fully automated randomized trial with two randomization branch-points. The first is inclusion of disease-specific orders in the admission orders based on a predictive model using...

Computer Aided Evaluation of Orbital Volume

A retrospective review to assess the performance and clinical predictive value of a novel software program (Maxillo) designed to perform complex volumetric analysis with application in the...

Radial accEss for nAvigation to Your CHosen Lesion for Peripheral Vascular Intervention: REACH PVI

The objective of this study is to evaluate acute clinical results of orbital atherectomy (OA) via radial artery access, including complication rates and cost effectiveness.

Medical and Biotech [MESH] Definitions

An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.

A nonspecific tumor-like inflammatory lesion in the ORBIT of the eye. It is usually composed of mature LYMPHOCYTES; PLASMA CELLS; MACROPHAGES; LEUKOCYTES with varying degrees of FIBROSIS. Orbital pseudotumors are often associated with inflammation of the extraocular muscles (ORBITAL MYOSITIS) or inflammation of the lacrimal glands (DACRYOADENITIS).

Inflammation of the extraocular muscle of the eye. It is characterized by swelling which can lead to ischemia, fibrosis, or ORBITAL PSEUDOTUMOR.

UNSATURATED FATTY ACIDS that contain at least one double bond in the trans configuration, which results in a greater bond angle than the cis configuration. This results in a more extended fatty acid chain similar to SATURATED FATTY ACIDS, with closer packing and reduced fluidity. HYDROGENATION of unsaturated fatty acids increases the trans content.

Rare disease characterized by COLOBOMA; CHOANAL ATRESIA; and abnormal SEMICIRCULAR CANALS. Mutations in CHD7 protein resulting in disturbed neural crest development are associated with CHARGE Syndrome.

Quick Search

DeepDyve research library

Searches Linking to this Article