Latest in cond-mat.str-el

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Measuring Electromagnetic and Gravitational Responses of Photonic Landau LevelsFeb 13 2018The topology of an object describes global properties that are insensitive to local perturbations. Classic examples include string knots and the genus (number of handles) of a surface: no manipulation of a closed string short of cutting it changes its ... More
Pair density wave, charge density wave and vortex in high Tc cupratesFeb 08 2018A recent scanning tunneling microscopy (STM) experiment reports the observation of charge density wave (CDW) with period of approximately 8a in the halo region surrounding the vortex core, in striking contrast to the approximately period 4a CDW that are ... More
Negative longitudinal magnetoresistance in the density wave phase of Y$_2$Ir$_2$O$_7$Feb 08 2018The ground state of nanowires of single crystalline Pyrochlore Y$_2$Ir$_2$O$_7$ is a density wave. Application of a {\it transverse} magnetic field increases the threshold electric field for the collective de-pinning of the density wave state at low temperature, ... More
Suppression and revival of long-range ferromagnetic order in the multiorbital Fermi-Hubbard modelFeb 08 2018By means of dynamical mean-field theory allowing for complete account of SU(2) rotational symmetry of interactions between spin-1/2 particles, we observe a strong effect of suppression of ferromagnetic order in the multiorbital Fermi-Hubbard model in ... More
Spin-Orbital Excitations in Ca$_{2}$RuO$_4$ Revealed by Resonant Inelastic X-ray ScatteringFeb 08 2018The strongly correlated insulator Ca$_{2}$RuO$_4$ is considered as a paradigmatic realization of both spin-orbital physics and a band-Mott insulating phase, characterized by orbitally selective coexistence of a band and a Mott gap. We present a high-resolution ... More
Numerical Algorithm for Exact Finite Temperature Spectra and Its Application to Frustrated Quantum Spin SystemsFeb 08 2018A numerical algorithm to calculate exact finite-temperature spectra of many-body lattice Hamiltonians is formulated by combining the typicality approach and the shifted Krylov subspace method. The combined algorithm, which we name finite-temperature shifted ... More
Weak doping dependence of the antiferromagnetic coupling between nearest-neighbor Mn$^{2+}$ spins in (Ba$_{1-x}$K$_x$)(Zn$_{1-y}$Mn$_y$)$_2$As$_2$Feb 08 2018Dilute magnetic semiconductors (DMS) are nonmagnetic semiconductors doped with magnetic transition metals. The recently discovered DMS material (Ba$_{1-x}$K$_{x}$)(Zn$_{1-y}$Mn$_{y}$)$_{2}$As$_{2}$ offers a unique and versatile control of the Curie temperature, ... More
Exotic Magnetism and Spin-Orbit Assisted Mott Insulating State in a $3d-5d$ Double PerovskiteFeb 08 2018The magnetic structure of Ca$_2$MnReO$_6$ double perovskite is investigated by neutron powder diffraction and bulk magnetization, showing dominant non-collinear Mn magnetic moments [$4.35(7)$ $\mu_B$] that are orthogonally aligned with the small Re moments ... More
Electronic and optical properties of La-doped Sr$_3$Ir$_2$O$_7$ epitaxial thin-filmsFeb 08 2018We have investigated structural, transport, and optical properties of tensile strained (Sr$_{1-x}$La$_x$)$_3$Ir$_2$O$_7$ (x = 0, 0.025, 0.05) epitaxial thin-films. While High-T$_c$ superconductivity is predicted theoretically in the system, we have observed ... More
Visualizing Heavy Fermion Confinement and Pauli-Limited Superconductivity in Layered CeCoIn5Feb 08 2018Layered material structures play a key role in enhancing electron-electron interactions to create correlated metallic phases that can transform into unconventional superconducting states. The quasi-two-dimensional electronic properties of such compounds ... More
Colossal magnetoresistance in a Mott insulator via magnetic field-driven insulator-metal transitionFeb 07 2018We present a new type of colossal magnetoresistance (CMR) arising from an anomalous collapse of the Mott insulating state via a modest magnetic field in a bilayer ruthenate, Ti-doped Ca$_3$Ru$_2$O$_7$. Such an insulator-metal transition is accompanied ... More
Lorentz breaking fixed points in Dirac and Weyl semimetalsFeb 07 2018We perform a renormalization group analysis of Coulomb interaction in anisotropic Weyl semimetals (non--circular or tilted Weyl cones). We find that the Fermi velocities and the speed of light do not reach a common value at the fixed point. Moreover, ... More
Landau theory for magnetic and structural transitions in CeCo$_{0.85}$Fe$_{0.15}$SiFeb 07 2018We present a phenomenological analysis of the magnetoelastic properties of CeCo$_{0.85}$Fe$_{0.15}$Si at temperatures close to the N\'eel transition temperature $T_N$. Using a Landau functional we provide a qualitative description of the thermal expansion, ... More
Quantum edge modes in 3d gravity and 2+1d topological phases of matterFeb 07 2018We analyze the edge mode structure of Euclidean three dimensional gravity from within the quantum theory as embodied by a Ponzano-Regge-Turaev-Viro discrete state sum with Gibbons-=-Hawking-York boundary conditions. This structure is encoded in a pair ... More
Orbital Transition in the Parent Spin-Orbit Mott Insulator Sr2IrO4Feb 07 2018The crystal lattice and vibrations of Sr2IrO4 were probed by a combined phonon Raman scattering and x-ray powder diffraction experiment at P < 45 GPa. Anomalies in phonon Raman intensities, energies and linewidths were observed at 17, 30 and 40 GPa with ... More
Low-Frequency Noise and Sliding of the Charge Density Waves in Two-Dimensional MaterialsFeb 07 2018There has been a recent renewal of interest in charge-density-wave (CDW) phenomena, primarily driven by the emergence of two-dimensional (2D) layered CDW materials, such as 1T-TaS2, characterized by very high transition temperatures to CDW phases. In ... More
Local Self-Energies for V and Pd Emergent from a Non-Local LDA+FLEX ImplementationFeb 07 2018In the spirit of recently developed LDA+U and LDA+DMFT methods we implement a combination of density functional theory in its local density approximation (LDA) with a $k$- and $\omega -$dependent self-energy found from diagrammatic fluctuational exchange ... More
Coupling between Spin and Charge Order Driven by Magnetic Field in Triangular Ising System LuFe2O4+δFeb 07 2018We present a study of the magnetic-field effect on spin correlations in the charge ordered triangular Ising system LuFe2O4+{\delta} through single crystal neutron diffraction. In the absence of a magnetic field, the strong diffuse neutron scattering observed ... More
Excitonic magnet in external field: complex order parameter and spin currentsFeb 07 2018We investigate spin-triplet exciton condensation in the two-orbital Hubbard model close to half filling by means of dynamical mean-field theory. Employing an impurity solver that handles complex off-diagonal hybridization functions, we study the behavior ... More
Natural Orbital-Based Lanczos Method for Anderson Impurity ModelsFeb 07 2018We implement the Lanczos algorithm on natural orbital basis to solve the zero-temperature Green's function of Anderson impurity models, following the work of Y. Lu, M. H\"{o}ppner, O. Gunnarsson, and M. W. Haverkort, Phys. Rev. B {\bf 90} (2014) 085102. ... More
From one-dimensional charge conserving superconductors to the gapless Haldane phaseFeb 07 2018We develop a framework to analyze one-dimensional topological superconductors with charge conservation. In particular, we consider models with $N$ flavors of fermions and $(\mathbb{Z}_2)^N$ symmetry, associated with the conservation of the fermionic parity ... More
Pressure dependence of coherence-incoherence crossover behavior in KFe2As2 observed by resistivity and 75As-NMR/NQRFeb 07 2018We present the results of $^{75}$As nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR), and resistivity measurements in KFe$_2$As$_2$ under pressure ($p$). The temperature dependence of the NMR shift, nuclear spin-lattice relaxation ... More
Visualizing Orbital-selective Quasiparticle Interference in the Hund's Metal State of FeSeFeb 06 2018High temperature superconductivity (HTS) in Cu-based materials is generated by strong electronic correlations due to proximity of the Mott insulator phase. By contrast, the undoped phase proximate to Fe-based HTS is never an insulator. But this striking ... More
Unitarity and Universality in non relativistic Conformal Field theoryFeb 06 2018We relate the notion of unitarity of a $SL(2,\mathbf{R})$ invariant field theory with that of a Schr\"odinger field theory using the fact that $SL(2,\mathbf{R})$ is a subgroup of Schr\"odinger group. Exploiting $SL(2,\mathbf{R})$ unitarity, we derive ... More
Stoner Instability of the Composite Fermi SeaFeb 06 2018We study two-component electrons in the lowest Landau level at total filling factor $\nu_T=1/2$ with anisotropic mass tensors and principal axes rotated by $\pi/2$ as realized in Aluminum Arsenide (AlAs) quantum wells. Combining exact diagonalization ... More
Dynamical synchronization transition in interacting electron systemsFeb 06 2018Using graphene irradiated by an intense bi-circular pulse laser as a prototypical example, we theoretically investigate how to selectively generate coherent oscillation of electronic orders such as charge density waves (CDW), where the key is to use tailored ... More
Building Symmetry Enriched Topological Phases from a Bipartite Lattice Construction and Anyon CondensationFeb 06 2018We introduce a construction of symmetry-enriched topological orders on bipartite lattices in which two $\mathbb{Z}_2$ spin liquids defined on each sublattice are combined, and then anyons are condensed to reduce the topological order. By choosing different ... More
$C$-$P$-$T$ anomaly in bosonic systemsFeb 06 2018We consider the $O(3)$ nonlinear sigma model with the $\theta$-term and its linear counterpart in 1+1D. The model has discrete time-reflection and space-reflection symmetries at any $\theta$, and enjoys the periodicity in $\theta\rightarrow \theta+2\pi$. ... More
Interacting birefringent electrons: Marginal- or non-Fermi liquid of spin-1/2 fermionsFeb 06 2018We present the quantum critical theory of an interacting nodal Fermi-liquid of quasi-relativisitc (pseudo)-spin-3/2 fermions that have a non-interacting \emph{birefringent} spectrum with \emph{two} distinct Fermi velocities. When such quasiparticles interact ... More
Locating the missing superconducting electrons in overdoped cupratesFeb 06 2018Overdoped high-temperature cuprate superconductors have been widely believed to be described by the physics of d-wave BCS-like superconductivity. However, recent measurements indicate that as the doping is increased, the superfluid density decreases smoothly ... More
New magnetic phase of the chiral skyrmion material Cu2OSeO3Feb 06 2018The lack of inversion symmetry in the crystal lattice of magnetic materials gives rise to complex non-collinear spin orders through interactions of relativistic nature, resulting in interesting physical phenomena, such as emergent electromagnetism. Studies ... More
Single crystal study of the charge density wave metal LuNiC2Feb 06 2018We report on single crystal growth, single crystal x-ray diffraction, physical properties and density functional theory (DFT) electronic structure as well as Fermi surface calculations for two orthorhombic ternary carbides, LuCoC2 and LuNiC2. Electrical ... More
Odd and even modes of neutron spin resonance in the bilayer iron-based superconductor CaKFe$_4$As$_4$Feb 06 2018We report an inelastic neutron scattering study on the neutron spin resonance in the bilayer iron-based superconductor CaKFe$_4$As$_4$. We discover strongly $L-$dependent triple spin resonance modes below $T_c=35$ K. The modes can be classified into odd ... More
Correlation strength, Lifshitz transition and the emergence of a two- to three-dimensional crossover in FeSe under pressureFeb 06 2018We report a detailed theoretical study of the electronic structure, spectral properties, and lattice parameters of bulk FeSe under pressure using a fully charge self-consistent implementation of the density functional theory plus dynamical mean-field ... More
Quantum many-body dynamics of the Einstein-de Haas effectFeb 05 2018In 1915, Einstein and de Haas and Barnett demonstrated that changing the magnetization of a magnetic material results in mechanical rotation, and vice versa. At the microscopic level, this effect governs the transfer between electron spin and orbital ... More
Pair Density Waves in Superconducting Vortex HalosFeb 05 2018We analyze the interplay between a d-wave uniform superconducting and a pair-density-wave (PDW) order parameter in the neighborhood of a vortex. We develop a phenomenological nonlinear sigma-model, solve the saddle point equation for the order parameter ... More
Experimental tests of the chiral anomaly magnetoresistance in the Dirac-Weyl semimetals Na$_3$Bi and GdPtBiFeb 05 2018In the Dirac/Weyl semimetal, the chiral anomaly appears as an "axial" current arising from charge-pumping between the lowest (chiral) Landau levels of the Weyl nodes, when an electric field is applied parallel to a magnetic field $\bf B$. Evidence for ... More
Discrete superconducting phases in FeSe-derived superconductorsFeb 05 2018A general feature of unconventional superconductors is the existence of a superconducting dome in the phase diagram as a function of carrier concentration. For the simplest iron-based superconductor FeSe (with transition temperature Tc ~ 8 K), its Tc ... More
Two-dimensional Type-II Dirac Fermions in Layered OxidesFeb 05 2018Relativistic massless Dirac fermions can be probed with high-energy physics experiments, but appear also as low-energy quasi-particle excitations in electronic band structures. In condensed matter systems, their massless nature can be protected by crystal ... More
Spin Hall effect in Rashba-Dresselhaus planar strips in the presence of electron correlationsFeb 03 2018A model with both Rashba and Dresselhaus spin orbit (SO) couplings and Hubbard electron-electron interaction is studied on planar strips at quarter filling at zero temperature in the clean limit. In the absence of Hubbard repulsion and at equilibrium, ... More
Spin-specific heat determination of the ratio of competing first- and second-neighbor exchange interactions in frustrated spin-$\frac{1}{2}$ chainsFeb 03 2018The magnetic susceptibility $\chi(T)$ of spin-1/2 chains is widely used to quantify exchange interactions, even though $\chi(T)$ is similar for different combinations of ferromagnetic $J_1$ between first neighbors and antiferromagnetic $J_2$ between second ... More
Randomness induced spin-liquid-like phase in the spin-$1/2$ $J_1 - J_2$ triangular Heisenberg modelFeb 03 2018We study the effects of bond randomness in the spin-$1/2$ $J_1-J_2$ triangular Heisenberg model using exact diagonalization and density matrix renormalization group. With increasing bond randomness, we identify a randomness induced disordered (RID) phase ... More
First-principles theory of magnetic multipoles in condensed matter systemsFeb 03 2018The multipole concept, which characterizes the spacial distribution of scalar and vector objects by their angular dependence, has already become widely used in various areas of physics. In recent years it has become employed to systematically classify ... More
Quantum phase diagram of spin-$1$ $J_1-J_2$ Heisenberg model on the square lattice: an infinite projected entangled-pair state and density matrix renormalization group studyFeb 02 2018We study the spin-$1$ Heisenberg model on the square lattice with the antiferromagnetic nearest-neighbor $J_1$ and the next-nearest-neighbor $J_2$ couplings by using the infinite projected entangled-pair state (iPEPS) ansatz and density matrix renormalization ... More
Controlling Nonequilibrium Kondo-vs-RKKY Scenarios in NanoclustersFeb 02 2018Ultrafast manipulations of magnetic phases are eliciting increasing attention from the scientific community, because potentially relevant to the understanding of nonequilibrium phase transitions and to novel technologies. Here, we focus on manipulations ... More
Quantum holography in a graphene flake with an irregular boundaryFeb 02 2018Electrons in clean macroscopic samples of graphene exhibit an astonishing variety of quantum phases when strong perpendicular magnetic field is applied. These include integer and fractional quantum Hall states as well as symmetry broken phases and quantum ... More
Topology of the Quantum Hall Effect. The Möbius strip modelFeb 02 2018Here we conjecture on a topological model based on the M\"obius strip derived from the current distribution at the plateaus of the Quantum Hall Effect (QHE). It can account for the fractional values of the QHE in an easy way.
Charge and current orders in the spin-fermion model with overlapping hot spotsFeb 02 2018Experiments carried over the last years on the underdoped cuprates have revealed a variety of symmetry-breaking phenomena in the pseudogap state. Charge-density waves, breaking of $C_{4}$ rotational symmetry as well as time-reversal symmetry breaking ... More
Correlated Insulator Behaviour at Half-Filling in Magic Angle Graphene SuperlatticesFeb 02 2018Van der Waals (vdW) heterostructures are an emergent class of metamaterials comprised of vertically stacked two-dimensional (2D) building blocks, which provide us with a vast tool set to engineer their properties on top of the already rich tunability ... More
$^{31}$P NMR study of discrete time-crystalline signatures in an ordered crystal of ammonium dihydrogen phosphateFeb 01 2018The rich dynamics and phase structure of driven systems includes the recently-described phenomenon of the "discrete time crystal" (DTC), a robust phase which spontaneously breaks the discrete time translation symmetry of its driving Hamiltonian. Experiments ... More
Phase diagram of the quantum Ising model with long-range interactions on an infinite-cylinder triangular latticeFeb 01 2018Obtaining quantitative ground-state behavior for geometrically-frustrated quantum magnets with long-range interactions is challenging for numerical methods. Here, we demonstrate that the ground states of these systems on two-dimensional lattices can be ... More
Two-color Fermi liquid theory for transport through a multilevel Kondo impurityFeb 01 2018Feb 08 2018We consider a quantum dot with ${\cal K}{\geq} 2$ orbital levels occupied by two electrons connected to two electric terminals. The generic model is given by a multi-level Anderson Hamiltonian. The weak-coupling theory at the particle-hole symmetric point ... More
Understanding the magnetism in noncentrosymmetric CeIrGe3: Muon spin relaxation and neutron scattering studiesFeb 01 2018The magnetic properties of a pressure induced noncentrosymmetric heavy-fermion superconductor CeIrGe$_3$ have been investigated by muon spin relaxation ($\mu$SR), powder neutron diffraction (ND) and inelastic neutron scattering (INS) techniques at ambient ... More
Fermion-induced quantum criticality with two length scales in Dirac systemsFeb 01 2018The quantum phase transition to a $\mathbb{Z}_3$-ordered Kekul\'e valence bond solid in two-dimensional Dirac semimetals is governed by a fermion-induced quantum critical point, which renders the putatively discontinuous transition continuous. We study ... More
Correlation-driven charge order in a frustrated two-dimensional atom latticeFeb 01 2018The triangular lattice of localised electrons is the canonical example for a geometrically frustrated spin arrangement. In conjunction with strong local Coulomb interactions, it leads to a competition of antiferromagnetic order and spin liquid behaviour. ... More
SU(4)-symmetric spin-orbital liquids on the hyperhoneycomb latticeJan 31 2018We study the effective spin-orbital model that describes the magnetism of 4$d^1$ or 5$d^1$ Mott insulators in ideal tricoordinated lattices. In the limit of vanishing Hund's coupling, the model has an emergent SU(4) symmetry which is made explicit by ... More
Exotic Superconductivity with Enhanced Energy Scales in Three Band Crossing MaterialsJan 31 2018Three band crossings can arise in three dimensional quantum materials with certain space group symmetries. The low energy Hamiltonian supports spin one fermions and a flat band. We study the pairing problem in this setting. We write down a minimal BCS ... More
Variational model for one-dimensional quantum magnetsJan 31 2018A new variational technique for investigation of the ground state and correlation functions in 1D quantum magnets is proposed. A spin Hamiltonian is reduced to a fermionic representation by the Jordan-Wigner transformation. The ground state is described ... More
Finite-temperature dynamic structure factor of the spin-1 XXZ chain with single-ion anisotropyJan 31 2018Feb 04 2018Improving matrix-product state techniques based on the purification of the density matrix, we are able to accurately calculate the finite-temperature dynamic response of the infinite spin-1 XXZ chain with single-ion anisotropy in the Haldane, large-$D$ ... More
Lattice dynamics of ASb2O6 (A=Cu,Co) with trirutile structureJan 31 2018Raman spectroscopy experiments on single crystals of CuSb2O6 and CoSb2O6 quasi-one-dimensional antiferromagnets with trirutile crystal structure were performed, with a focus on the first material. The observed Raman-active phonon modes and previously ... More
Non-Fermi surface nesting driven commensurate magnetic ordering in Fe-doped Sr$_2$RuO$_4$Jan 31 2018Sr$_2$RuO$_4$, an unconventional superconductor, is known to possess an incommensurate spin density wave instability driven by Fermi surface nesting. Here we report a static spin density wave ordering with a commensurate propagation vector $q_c$ = (0.25 ... More
The Heisenberg spin-1/2 XXZ chain in the presence of electric and magnetic fieldsJan 31 2018We study the interplay of electric and magnetic order in the one dimensional Heisenberg spin-1/2 XXZ chain with large Ising anisotropy in the presence of the Dzyaloshinskii-Moriya (D-M) interaction and with longitudinal and transverse magnetic fields, ... More
Coupled magnetic and ferroelectric states in the distorted honeycomb system Fe$_{4}$Ta$_{2}$O$_{9}$Jan 31 2018We report on the magnetic, thermodynamic, dielectric, and pyroelectric measurements on the hitherto unreported Fe${_4}$Ta${_2}$O${_9}$. This system is seen to exhibit a series of magnetic transitions, many of which are coupled to the emergence of ferroelectric ... More
Interplay of Itinerant and Localized Spin Fluctuations in the Ferromagnetic Superconductor UGe$_2$Jan 31 2018Microscopic coexistence of ferromagnetism and unconventional superconductivity renders UGe$_2$ a candidate for spin-triplet superconductivity. To avoid pair-breaking, spin-triplet superconductivity is mediated by longitudinal spin fluctuations promoted ... More
Magnetic order in the quantum spin chain compound SrCo$_{2}$V$_{2}$O$_{8}$: a single-crystal neutron diffraction study in magnetic fieldJan 30 2018We explore the spin states in the quantum spin chain compound SrCo$_{2}$V$_{2}$O$_{8}$ up to 14.9 T and down to 50 mK, using single-crystal neutron diffraction. Upon cooling in zero-field, antiferromagnetic (AFM) order of N\'eel type develops at $T_\mathrm{{N}}$ ... More
w2dynamics: Local one- and two-particle quantities from dynamical mean field theoryJan 30 2018We describe the hybridization-expansion continuous-time quantum Monte Carlo code package "w2dynamics", developed in Wien and W\"urzburg. We discuss the main features of this multi-orbital quantum impurity solver for the Anderson impurity model, dynamical ... More
Structural and electronic phase transitions in FePS$_3$ under the application of pressureJan 30 2018Two-dimensional materials have proven to be a prolific breeding ground of new and unstudied forms of magnetism and unusual metallic states, particularly when tuned between their insulating and metallic phases. In this paper we present work on a new metal ... More
Volume and Topological Invariants of Quantum Many-body SystemsJan 30 2018A gapped many-body system is described by path integral on a space-time lattice $C^{d+1}$, which gives rise to a partition function $Z(C^{d+1})$ if $\partial C^{d+1} =\emptyset$, and gives rise to a vector $|\Psi\rangle$ on the boundary of space-time ... More
Spin dynamics and exchange interactions in CuO measured by neutron scatteringJan 29 2018The magnetic properties of CuO encompass several contemporary themes in condensed matter physics, including quantum magnetism, magnetic frustration, magnetically-induced ferroelectricity and orbital currents. Here we report polarized and unpolarized neutron ... More
Quantum metric contribution to the pair mass in spin-orbit coupled Fermi superfluidsJan 29 2018As a measure of the quantum distance between Bloch states in the Hilbert space, the quantum metric was introduced to solid-state physics through the real part of the so-called geometric Fubini-Study tensor, the imaginary part of which corresponds to the ... More
Enhanced moments of Eu in single crystals of the metallic helical antiferromagnet EuCo{2-y}As2Jan 26 2018The compound EuCo{2-y}As2 with the tetragonal ThCr2Si2 structure is known to contain Eu{+2} ions with spin S = 7/2 that order below a temperature TN = 47 K into an antiferromagnetic (AFM) proper helical structure with the ordered moments aligned in the ... More
Probing magnetism in 2D van der Waals crystalline insulators via electron tunnelingJan 26 2018Magnetic insulators are a key resource for next-generation spintronic and topological devices. The family of layered metal halides promises ultrathin insulating multiferroics, spin liquids, and ferromagnets, but new characterization methods are required ... More
R-matrix-valued Lax pairs and long-range spin chainsJan 26 2018In this paper we discuss $R$-matrix-valued Lax pairs for ${\rm sl}_N$ Calogero-Moser model and its relation to integrable quantum long-range spin chain of the Haldane-Shastry-Inozemtsev type. First, we construct the $R$-matrix-valued Lax pairs for the ... More
Uncovering the mechanism of the impurity-selective Mott transition in paramagnetic V$_{2}$O$_{3}$Jan 26 2018While the phase diagrams of the one- and multi-orbital Hubbard model have been well studied, the physics of real Mott insulators is often much richer, material dependent, and poorly understood. In the prototype Mott insulator V$_2$O$_3$, chemical pressure ... More
Viscosity Bound Violation in Viscoelastic Fermi LiquidsJan 25 2018The anti-de Sitter/conformal field theory correspondence (AdS/CFT) has been used to determine the lower bound of the shear viscosity to entropy density ratio for strongly-coupled field theories with a gravity dual. The universal lower bound, given as ... More
Precise extrapolation of the correlation function asymptotics in uniform tensor network states with application to the Bose-Hubbard and XXZ modelsJan 25 2018We analyze the problem of extracting the correlation length from infinite matrix product states (MPS) and corner transfer matrix (CTM) simulations. When the correlation length is calculated directly from the transfer matrix, it is typically significantly ... More
Anisotropic fluctuations in cool quark matter and the phase diagram of Quantum ChromodynamicsJan 24 2018In cool quark matter, at intermediate densities the excitations of single quarks are confined ("quarkyonic"). A long ranged confining potential reduces the scattering of such quarks to be essentially one dimensional. As a result the Fermi surface, which ... More
Robustness of the charge-ordered phases in IrTe$_2$ against photoexcitationJan 24 2018We present a time-resolved angle-resolved photoelectron spectroscopy study of IrTe$_2$, which undergoes two first-order structural and charge-ordered phase transitions on cooling below 270 K and below 180 K. The possibility of inducing a phase transition ... More
Bimeron nanoconfined designJan 24 2018We report on the stabilization of the topological bimeron excitations in confined geometries. The Monte Carlo simulations for a ferromagnet with a strong Dzyaloshinskii-Moriya interaction revealed the formation of a mixed skyrmion-bimeron phase. The vacancy ... More
Band dependent inter-layer $f$-electron hybridization in CeRhIn$_5$Jan 23 2018A key issue in heavy fermion research is how subtle changes in the hybridization between the 4$f$ (5$f$) and conduction electrons can result in fundamentally different ground states. CeRhIn$_5$ stands out as a particularly notable example: replacing Rh ... More
Universal theory of one-dimensional quantum liquids with finite-range interactionsJan 23 2018The universal theory for the high-energy spectral properties of a wide class of one-dimensional correlated systems based on the mobile-quantum-impurity model has not been extended to finite-range interactions. Here that problem is addressed by adding ... More
Many-body localization, symmetry, and topologyJan 23 2018We review recent developments in the study of out-of-equilibrium topological states of matter in isolated systems. The phenomenon of many-body localization, exhibited by some isolated systems usually in the presence of quenched disorder, prevents systems ... More
Time-dependent generalized Gibbs ensembles in open quantum systemsJan 23 2018Generalized Gibbs ensembles have been used as powerful tools to describe the steady state of integrable many-particle quantum systems after a sudden change of the Hamiltonian. Here we demonstrate numerically, that they can be used for a much broader class ... More
Photoemission response of 2D statesJan 23 2018A lucid formalism based on Fourier transform description of the photoemission process is presented that directly relates photon energy dependent ARPES response of two-dimensional (2D) electron states to their wavefunctions. The states formed by quantum ... More
Quantum oscillations and Dirac dispersion in the BaZnBi2 semimetal enhanced by local Zn vacancy orderJan 23 2018We have synthesized single crystals of Dirac semimetal candidates AZnBi2 with A=Ba and Sr. In contrast to A=Sr, the Ba material displays a novel local Zn vacancy ordering, which makes the observation of quantum oscillations in out-of-plane magnetic fields ... More
Charge Kondo Effect and Superconductivity in the Falikov-Kimball model with the Pair HoppingJan 23 2018We study the Falikov-Kimball model with the pair hopping between the conduction and localized bands to discuss how the charge Kondo effect is realized. By combining dynamical mean-field theory with the continuous time quantum Monte Carlo method, we clarify ... More
The quasi-periodic quantum Ising transition in 1DJan 22 2018Unlike random potentials, quasi-periodic modulation can induce localisation-delocalisation transitions in one dimension. In this article, we analyse the implications of this for symmetry breaking in the quasi-periodically modulated quantum Ising chain. ... More
Pressure induced BEC-BCS crossover in multi-band superconductorsJan 22 2018Superconductivity in strongly correlated systems is a remarkable phenomenon that attracts a huge interest. The study of this problem is relevant for materials as the high $T_c$ oxides, pnictides and heavy fermions. These systems also have in common the ... More
Renormalization group approach to symmetry protected topological phasesJan 22 2018A defining feature of a symmetry protected topological phase (SPT) in one-dimension is the degeneracy of the Schmidt values for any given bipartition. For the system to go through a topological phase transition separating two SPTs, the Schmidt values ... More
Role of quantum fluctuations on spin liquids and ordered phases in the Heisenberg model on the honeycomb latticeJan 22 2018Motivated by the rich physics of honeycomb magnetic materials, we obtain the phase diagram and analyze magnetic properties of the spin-1/2 and spin-1 J1-J2-J3 Heisenberg model on the honeycomb lattice. Based on the SU(2) and SU(3) symmetry representations ... More
Localization of magnon modes in a curved magnetic nanowireJan 22 2018Spin waves in magnetic nanowires can be bound by a local bending of the wire. The eigenfrequency of a truly local magnon mode is determined by the curvature: a general analytical expression is established for any infinitesimally weak localized curvature ... More
Unveiling the phase diagram of a striped cuprate at high magnetic fields: Hidden order of Cooper pairsJan 21 2018The interplay of charge orders with superconductivity in underdoped cuprates at high magnetic fields ($H$) is an open question, and even the value of the upper critical field ($H_{c2}$), a measure of the strength of superconductivity, has been the subject ... More
Floquet Engineering in Quantum ChainsJan 21 2018We consider a one-dimensional interacting spinless fermion model, which displays the well-known Luttinger liquid (LL) to charge density wave (CDW) transition as a function of the ratio between the strength of the interaction, $U$, and the hopping, $J$. ... More
Polarized-neutron investigation of magnetic ordering and spin dynamics in BaCo$_2$(AsO$_4$)$_2$ frustrated honeycomb-lattice magnetJan 19 2018The magnetic properties of the cobaltite {\BCAO}, a good realization of the quasi two-dimensional frustrated honeycomb-lattice system with strong planar anisotropy, have been reinvestigated by means of spherical neutron polarimetry with CRYOPAD. From ... More
The Conditions for $l=1$ Pomeranchuk Instability in a Fermi LiquidJan 19 2018We perform a microscropic analysis of how the constraints imposed by conservation laws affect $q=0$ Pomeranchuk instabilities in a Fermi liquid. The conventional view is that these instabilities are determined by the static interaction between low-energy ... More
Soft antiphase tilt of oxygen octahedra in the hybrid improper multiferroic Ca3Mn1.9Ti0.1O7Jan 19 2018We report a single crystal neutron and x-ray diffraction study of the hybrid improper multiferroic Ca3Mn1.9Ti0.1O7 (CMTO), a prototypical system where the electric polarization arises from the condensation of two lattice distortion modes.With increasing ... More
Turning Copper Metal into Weyl SemimetalJan 18 2018A search for new topological quantum systems is challenging due to the requirement of non-trivial band connectivity that leads to protected surface states of electrons. A progress in this field was primarily due to a realization of band inversion mechanism ... More
The Uniform Electron Gas at Warm Dense Matter ConditionsJan 17 2018We review the uniform electron gas (UEG) at finite temperature and over a broad density range relevant for warm dense matter (WDM) applications. We provide an overview of different simulation techniques, focusing on recent developments in the dielectric ... More
Single crystal growth of Cu4(OH)6BrF and universal behavior in quantum spin liquid candidates synthetic barlowite and herbertsmithiteJan 17 2018Synthetic barlowite, Cu4(OH)6BrF, has emerged as a new quantum spin liquid (QSL) host, containing kagome layers of S=1/2 Cu2+ ions separated by interlayer Cu2+ ions. Similar to synthetic herbertsmithite, ZnCu3(OH)6Cl2, it has been reported that Zn2+ substitution ... More
Evidence of an improper displacive phase transition in Cd$_2$Re$_2$O$_7$ via time-resolved coherent phonon spectroscopyJan 16 2018We have used a combination of ultrafast coherent phonon spectroscopy, ultrafast thermometry, and time-dependent Landau theory to study the inversion symmetry breaking phase transition at $T_c = 200$ K in the strongly spin-orbit coupled correlated metal ... More