A precise method for visualizing dispersive features in image plots

Zhang, P.; Richard, P.; Qian, Tao; Xu, Yueren; Dai, Xi; Ding, Hao

doi:10.1063/1.3585113

Cited by 267 publications

(186 citation statements)

References 34 publications

Supporting

Mentioning

180

Contrasting

Unclassified

Order By: Relevance

“…Спершу для візуалізації дисперсії зон широко використовувалася метода другої похідної [20], яку було вдосконалено у методі криви-ни [21].…”

Section: вступunclassified

“…Емпі-рично було встановлено, що найліпші результати можна одержати, коли C 0 порядку середнього або максимального значення 2 | ( )| . f x ′ Оскільки потрібно шукати позицію піку (максимуму), то необхідно враховувати від'ємну частину знакозмінних других похідних [21].…”

Section: метода кривиниunclassified

See 1 more Smart Citation

Temperature Dependence of the Electronic Structure of FeSe

Pustovit¹,

Bezguba²,

Kordyuk³

2017

Metallofiz. Noveishie Tekhnol.

View full text Add to dashboard Cite

Характерною загальною особливістю електронної структури надпровід-ників на основі заліза є систематичний зсув реальних електронних зон у порівнянні з розрахованими, який, ймовірно, пов'язаний із міжелект-ронною взаємодією. У ряді недавніх робіт було висловлено гіпотезу, що цей зсув разом із величиною взаємодії мають зменшуватися зі збільшен-ням температури, а також наведено експериментальні дані на її підтрим-ку. Ми детально дослідили еволюцію електронної структури FeSe від 20 до 250 К та прийшли до висновку, що зсув із температурою d xy -зони в центрі Бріллюенової зони приводить до протилежного ефекту -енергія зв'язку d xy -електронів збільшується з ростом температури.Ключові слова: електронна спектроскопія з кутовою роздільчою здатніс-тю, електронна структура FeSe, надпровідники на основі заліза, метода кривини.A characteristic feature of the electronic structure of iron-based superconductors is the shift of experimental electronic bands in comparison to the results of calculations. This shift is most likely a result of electron-electron interaction. In some recent papers, a hypothesis that the shift, together with

show abstract

Section: вступunclassified

Section: метода кривиниunclassified

Temperature Dependence of the Electronic Structure of FeSe

Pustovit¹,

Bezguba²,

Kordyuk³

2017

Metallofiz. Noveishie Tekhnol.

View full text Add to dashboard Cite

show abstract

“…For the experimental data, we applied the 2D curvature method for clarity [34]. The kz for the measured electron pockets is not exactly at 0 or π as the data was taken on a constant total momentum surface (fixed photon energy).…”

Section: Fig 2: (Color Online) Dmft (Solid Lines) and Dft (Dashed)mentioning

confidence: 99%

Orbital Selective Fermi Surface Shifts and Mechanism of HighTcSuperconductivity in CorrelatedAFeAs(A=Li, Na)

Lee

Kim

et al. 2012

Phys. Rev. Lett.

View full text Add to dashboard Cite

Based on the dynamical mean field theory (DMFT) and angle resolved photoemission spectroscopy (ARPES), we have investigated the mechanism of high Tc superconductivity in stoichiometric LiFeAs. The calculated spectrum is in excellent agreement with the observed ARPES measurement. The Fermi surface (FS) nesting, which is predicted in the conventional density functional theory method, is suppressed due to the orbital-dependent correlation effect with the DMFT method. We have shown that such marginal breakdown of the FS nesting is an essential condition to the spin-fluctuation mediated superconductivity, while the good FS nesting in NaFeAs induces a spin density wave ground state. Our results indicate that fully charge self-consistent description of the correlation effect is crucial in the description of the FS nesting-driven instabilities.

show abstract

“…Figure 2a1-a5 displays intensity maps taken at constant energies between −200 to −400 meV. Corresponding curvature plots 26 are used to highlight dispersive bands in ARPES data ( Fig. 2b1-b5).…”

mentioning

confidence: 99%

Gaps induced by inversion symmetry breaking and second-generation Dirac cones in graphene/hexagonal boron nitride

et al. 2016

View full text Add to dashboard Cite

Graphene/hexagonal boron nitride (h-BN) has emerged as a model van der Waals heterostructure 1 as the superlattice potential, which is induced by lattice mismatch and crystal orientation, gives rise to various novel quantum phenomena, such as the self-similar Hofstadter butterfly states 2-5 . Although the newly generated second-generation Dirac cones (SDCs) are believed to be crucial for understanding such intriguing phenomena, fundamental knowledge of SDCs, such as locations and dispersion, and the e ect of inversion symmetry breaking on the gap opening, still remains highly debated due to the lack of direct experimental results. Here we report direct experimental results on the dispersion of SDCs in 0 • -aligned graphene/h-BN heterostructures using angle-resolved photoemission spectroscopy. Our data unambiguously reveal SDCs at the corners of the superlattice Brillouin zone, and at only one of the two superlattice valleys. Moreover, gaps of approximately 100 meV and approximately 160 meV are observed at the SDCs and the original graphene Dirac cone, respectively. Our work highlights the important role of a strong inversion-symmetry-breaking perturbation potential in the physics of graphene/h-BN, and fills critical knowledge gaps in the band structure engineering of Dirac fermions by a superlattice potential.Hexagonal boron nitride (h-BN) shares a similar honeycomb lattice structure to graphene, yet its lattice is stretched by 1.8%. Moreover, the breaking of the inversion symmetry by distinct boron and nitrogen sublattices leads to a large bandgap (5.97 eV) in the π band, which is in sharp contrast to the gapless Dirac cones in graphene. By stacking graphene atop h-BN to form a van der Waals heterostructure 1 , graphene/h-BN not only exhibits greatly improved properties for device applications, such as reduced ripples, suppressed charge inhomogeneities and higher mobility 6,7 , but also provides unique opportunities for band structure engineering of Dirac fermions by a periodic potential 8,9 . The superlattice potential induced by the lattice mismatch and crystal orientation can significantly modify the electronic properties of graphene and lead to various novel quantum phenomena, for example, the emergence of second-generation Dirac cones (SDCs), which are crucial for the realization of Hofstadter butterfly states under an applied magnetic field 2-5 , renormalization of the Fermi velocity 8,[10][11][12] , gap opening at the Dirac point 4,13-16 , topological currents 15 and gate-dependent pseudospin mixing 17 . Hence, understanding the effects of the superlattice potential on the band structure of graphene is crucial for advancing its device applications, and for gaining new knowledge about the fundamental physics of Dirac fermions in a periodic potential.Previously, the existence of SDCs has been deduced from scanning tunnelling spectroscopy, resistivity and capacitance measurements 2,5,18,19 . However, such measurements are not capable of mapping out the electronic dispersion with momentum-resolved informatio...

show abstract

A precise method for visualizing dispersive features in image plots

Cited by 267 publications

References 34 publications

Temperature Dependence of the Electronic Structure of FeSe

Temperature Dependence of the Electronic Structure of FeSe

Orbital Selective Fermi Surface Shifts and Mechanism of HighTcSuperconductivity in CorrelatedAFeAs(A=Li, Na)

Gaps induced by inversion symmetry breaking and second-generation Dirac cones in graphene/hexagonal boron nitride

Contact Info

Product

Resources

About