Angle-dependent magnetoresistance and its implications for Lifshitz transition in W2As3

AbstractLifshitz transition represents a sudden reconstruction of Fermi surface structure, giving rise to anomalies in electronic properties of materials. Such a transition does not necessarily rely on symmetry-breaking and thus is topological. It holds a key to understand the origin of many exotic quantum phenomena, for example, the mechanism of extremely large magnetoresistance (MR) in topological Dirac/Weyl semimetals. Here, we report studies of the angle-dependent MR (ADMR) and the thermoelectric effect in W2As3 single crystal. The compound shows a large unsaturated MR (of about 7000% at 4.2 K and 53 T). The most striking finding is that the ADMR significantly deforms from the horizontal dumbbell-like shape above 40 K to the vertical lotus-like pattern below 30 K. The window of 30–40 K also corresponds substantial changes in Hall effect, thermopower and Nernst coefficient, implying an abrupt change of Fermi surface topology. Such a temperature-induced Lifshitz transition results in a compensation of electron-hole transport and the large MR as well. We thus suggest that the similar method can be applicable in detecting a Fermi-surface change of a variety of quantum states when a direct Fermi-surface measurement is not possible.

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Ultrafast dynamical Lifshitz transition

Science Advances ◽

10.1126/sciadv.abd9275 ◽

2021 ◽

Vol 7 (17) ◽

pp. eabd9275

Author(s):

Samuel Beaulieu ◽

Shuo Dong ◽

Nicolas Tancogne-Dejean ◽

Maciej Dendzik ◽

Tommaso Pincelli ◽

...

Keyword(s):

Fermi Surface ◽

Colossal Magnetoresistance ◽

Surface Topology ◽

Strongly Correlated ◽

Many Body ◽

Time Resolved ◽

Weyl Semimetal ◽

Lifshitz Transition ◽

Fermi Surface Topology ◽

Many Body Systems

Fermi surface is at the heart of our understanding of metals and strongly correlated many-body systems. An abrupt change in the Fermi surface topology, also called Lifshitz transition, can lead to the emergence of fascinating phenomena like colossal magnetoresistance and superconductivity. While Lifshitz transitions have been demonstrated for a broad range of materials by equilibrium tuning of macroscopic parameters such as strain, doping, pressure, and temperature, a nonequilibrium dynamical route toward ultrafast modification of the Fermi surface topology has not been experimentally demonstrated. Combining time-resolved multidimensional photoemission spectroscopy with state-of-the-art TDDFT+U simulations, we introduce a scheme for driving an ultrafast Lifshitz transition in the correlated type-II Weyl semimetal Td-MoTe2. We demonstrate that this nonequilibrium topological electronic transition finds its microscopic origin in the dynamical modification of the effective electronic correlations. These results shed light on a previously unexplored ultrafast scheme for controlling the Fermi surface topology in correlated quantum materials.

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Tunable Fermi surface topology and Lifshitz transition in bilayer graphene

Synthetic Metals ◽

10.1016/j.synthmet.2015.07.006 ◽

2015 ◽

Vol 210 ◽

pp. 19-31 ◽

Cited By ~ 11

Author(s):

Anastasia Varlet ◽

Marcin Mucha-Kruczyński ◽

Dominik Bischoff ◽

Pauline Simonet ◽

Takashi Taniguchi ◽

...

Keyword(s):

Fermi Surface ◽

Bilayer Graphene ◽

Surface Topology ◽

Lifshitz Transition ◽

Fermi Surface Topology

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Controlling a Van Hove singularity and Fermi surface topology at a complex oxide heterostructure interface

Nature Communications ◽

10.1038/s41467-019-13046-z ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Ryo Mori ◽

Patrick B. Marshall ◽

Kaveh Ahadi ◽

Jonathan D. Denlinger ◽

Susanne Stemmer ◽

...

Keyword(s):

Fermi Surface ◽

Quantum Confinement ◽

Complex Oxide ◽

Surface Topology ◽

Chemical Doping ◽

Lifshitz Transition ◽

Band Insulator ◽

Fine Control ◽

Fermi Surface Topology ◽

Oxide Heterostructure

AbstractThe emergence of saddle-point Van Hove singularities (VHSs) in the density of states, accompanied by a change in Fermi surface topology, Lifshitz transition, constitutes an ideal ground for the emergence of different electronic phenomena, such as superconductivity, pseudo-gap, magnetism, and density waves. However, in most materials the Fermi level, $${E}_{{\rm{F}}}$$EF, is too far from the VHS where the change of electronic topology takes place, making it difficult to reach with standard chemical doping or gating techniques. Here, we demonstrate that this scenario can be realized at the interface between a Mott insulator and a band insulator as a result of quantum confinement and correlation enhancement, and easily tuned by fine control of layer thickness and orbital occupancy. These results provide a tunable pathway for Fermi surface topology and VHS engineering of electronic phases.

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