Bulletin of the American Physical Society
APS March Meeting 2015
Volume 60, Number 1
Monday–Friday, March 2–6, 2015; San Antonio, Texas
Session A11: Cuprate Superconductivity: Charge Density Waves and Charge Order |
Hide Abstracts |
Sponsoring Units: DCMP Chair: Wei Ku, Brookhaven National Laboratory Room: 007B |
Monday, March 2, 2015 8:00AM - 8:12AM |
A11.00001: Origin of charge density wave instability in the underdoped cuprates Vivek Mishra, M. R. Norman The exact nature of the normal state in the underdoped cuprates is still debatable. Recent experimental results favor the existence of an unconventional charge density wave with d-wave form factor above the superconducting transition. Here we study the charge density wave instability within the Eliashberg framework. We find the full momentum structure of the leading charge density wave order and compare its strength to the superconductivity driven by spin-fluctuation mediated pairing interaction. [Preview Abstract] |
Monday, March 2, 2015 8:12AM - 8:24AM |
A11.00002: ABSTRACT WITHDRAWN |
Monday, March 2, 2015 8:24AM - 8:36AM |
A11.00003: Interplay between pair-density-wave and charge-density-wave orders in underdoped cuprates Daniel Agterberg, Yuxuan Wang, Andrey Chubukov We analyze the interplay between charge-density-wave (CDW) and pair-density-wave (PDW) orders within the spin-fermion model for the cuprates. We show that both orders do emerge in the spin-fermion model as preemptive orders to antiferromagnetism, and are constructed out of pairs of ``hot'' fermions on the Fermi surface. We that the two orders are nearly degenerate and are related by an approximate SU(2) particle-hole symmetry of the spin-fermion model. The SU(2) symmetry is exact if one neglects the curvature of the Fermi surface in hot regions, in which case the CDW and PDW, each breaking translational U(1) symmetry, become components of an O(4)-symmetric super-vector. We show that the curvature of the Fermi surface breaks this degeneracy and that the mean-field transition temperature is higher for the PDW order. However, we also argue that both CDW and PDW order break additional discrete $Z_2$ symmetries and show that the feedback from $Z_2$ order on the CDW order is stronger. This feedback increases the critical temperature for CDW order compared to that for PDW order. Which state develops first depends on system parameters. We also consider the case when both orders are present at low $T$ and argue that simultaneous presence of CDW and PDW orders induce a variety of states. [Preview Abstract] |
Monday, March 2, 2015 8:36AM - 8:48AM |
A11.00004: Composite Charge Order In Cuprate Superconductors Andrey Chubukov, Yuxuan Wang We analyze charge order in hole-doped cuprates. We argue that magnetically-mediated interaction, which is known to give rise to d-wave superconductivity, also gives rise to charge-density-wave instabilities with momenta $Q_x =(Q,0)$ and $Q_y =(0,Q)$, as seen in the experiments. We show that the emerging charge order with $Q_x/Q_y$ is of stripe type and that a stripe charge order parameter by itself has two components: one is incommensurate density variation, another is incommensurate current. Both components are non-zero in the CDW-ordered state, with the relative phase $\pm\pi/2$. Such an order breaks time reversal symmetry. We further show that, before a true incommensurate CDW order sets in, the system develops a pre-emptive composite order which breaks lattice rotational symmetry and time-reversal symmetry but preserves a translational $U(1)$ symmetry. We discuss the interplay between our CDW order and superconductivity and the spin-fluctuation scenario for the pseudogap phase. [Preview Abstract] |
Monday, March 2, 2015 8:48AM - 9:00AM |
A11.00005: Ginzburg-Landau Theory of multi-component order parameter in the cuprate pseudo-gap regime Laimei Nie, Subir Sachdev, Steven Kivelson We study a Landau-Ginzburg-Wilson effective field theory of a quasi-2D system with potential disorder in which incommensurate charge-density wave and superconducting orders are intertwined. The model is shown to exhibit a rich phase diagram at a large-N mean-field level, where both superconducting and nematic, but not charge-density wave order, can persist in the presence of the quenched disorder. We select three representative sets of input parameters and compute the corresponding CDW structure factors. Where nematicity and SC coexist, the peak height of the CDW structure factor decreases monotonically as a function of increasing T, unlike what is seen in X-ray experiments in YBCO. In the parameter regime where no nematic phase occurs, we compute to one-loop order the nematic correlation length, which is shown to be much shorter than CDW correlation length. [Preview Abstract] |
Monday, March 2, 2015 9:00AM - 9:12AM |
A11.00006: Quasiparticle transport coefficients from a mean field bond density wave state in high-Tc cuprates Girish Sharma, Kangjun Seo, Sumanta Tewari The pseudogap regime in low hole doped high Tc cuprate superconductors exhibits peculiar experimental signatures like the detection of enhanced negative signals for Hall, Seebeck and Nernst coefficients. This has been ascribed to a competing density wave order with superconductivity near 1/8 hold doping and low temperature regimes. Starting with a mean field quasiparticle model describing a bi-axial bond density wave (BDW) state with Q1 = (0, 2?/3) and Q2 = (2?/3, 0), we show that the Fermi surface is reconstructed with the emergence of electron and hole-like pockets in the Brillouin zone. Employing semi-classical Boltzmann dynamics, the emergence of an enhanced negative Hall, Seebeck and Nernst coefficients is shown which is consistent with experimental data. This type of response is not seen for a uni-axial BDW order of type Q1 or Q2. [Preview Abstract] |
Monday, March 2, 2015 9:12AM - 9:24AM |
A11.00007: Monte Carlo studies of diamagnetism and charge density wave order in the cuprate pseudogap regime Lauren Hayward Sierens, Andrew Achkar, David Hawthorn, Roger Melko, Subir Sachdev The pseudogap regime of the hole-doped cuprate superconductors is often characterized experimentally in terms of a substantial diamagnetic response and, from another point of view, in terms of strong charge density wave (CDW) order. We introduce a dimensionless ratio, $R$, that incorporates both diamagnetic susceptibility and the correlation length of CDW order, and therefore reconciles these two fundamental characteristics of the pseudogap [PRB 90, 094515 (2014)]. We perform Monte Carlo simulations on a classical model that considers angular fluctuations of a six-dimensional order parameter [Science 343, 1336 (2014)], and compare our Monte Carlo results for $R$ with existing data from torque magnetometry and x-ray scattering experiments on YBa$_2$Cu$_3$O$_{6+x}$. We achieve qualitative agreement, and also propose future experiments to further investigate the behaviour of this dimensionless ratio. [Preview Abstract] |
Monday, March 2, 2015 9:24AM - 9:36AM |
A11.00008: The charge susceptibility in the cuprate pseudogap phase: Similiarities and differences between Fermi pockets and Fermi arcs scenarios Peter Scherpelz, Adam Rancon, Yan He, K. Levin Recent experimental results have provided a variety of evidence for incommensurate charge ordering in underdoped cuprates. To understand these experimental findings, here we address the calculation of charge response functions. We perform these calculations for both the Fermi arcs approach, and the Fermi pockets scenario of Yang, Rice, and Zhang. Critically, we include vertex corrections that have previously been omitted, and which are shown to exactly satisfy the sum rules. We show that these corrections lead to a double-peak structure in the susceptibility, as well as significant suppression of the susceptibility for low $q$. These effects have a straightforward physical interpretation: They represent the inclusion of charged bosonic, spin singlet degrees of freedom. See also Scherpelz et al., PRB 90 060506(R) (2014). [Preview Abstract] |
Monday, March 2, 2015 9:36AM - 9:48AM |
A11.00009: Fully consistent theory of response functions in the cuprate pseudogap phase: Implementing the Ward Takahashi identity Chien-Te Wu, Rufus Boyack, Peter Scherpelz, Kathryn Levin There is a multiplicity of pairing-based theories of the cuprate pseudogap associated with Fermi surface reconstruction or charge ordering, which have a simple mean-field-like self energy. These include the scenario of Yang, Rice and Zhang and the recent Amperean pairing scenario of Lee. We demonstrate here how to arrive at precise response functions for this class of theories which include vertex corrections, where necessary. Thus one can address two body physics experiments at the same level of accuracy that one addresses the one body physics of photoemission spectroscopy. We do so by exploiting the Ward Takahashi identity. As an illustration, we present the spin dynamical response functions of neutron scattering for three different scenarios, finding that a recently proposed pair Amperean pairing scheme is readily distinguishable from other related scenarios. [Preview Abstract] |
Monday, March 2, 2015 9:48AM - 10:00AM |
A11.00010: Emergent loop current order from pair density wave superconductivity Manoj Kashyap, Drew Melchert, Daniel Agterberg In addition to charge density wave (CDW) order, there is evidence that the pseudogap phase in the cuprates breaks time reversal symmetry. Here we show that pair density wave (PDW) states give rise to a translational invariant non-superconducting order parameter that breaks time reversal and parity symmetries, but preserves their product. This secondary order parameter has a different origin, but shares the same symmetry properties as a magnetoelectric loop current order that has been proposed earlier in the context of the cuprates to explain the appearance of intra-cell magnetic order. We further show that, due to fluctuations, this secondary loop current order, which represents the breaking of discrete symmetries, can preempt PDW order, which breaks both continuous and discrete symmetries. In such a phase, the emergent loop current order coexists with spatial short range CDW and short range superconducting order. Finally, we propose a PDW phase that accounts for intra-cell magnetic order and the Kerr effect, has CDW order consistent with x-ray scattering and nuclear magnetic resonance observations, and quasi-particle properties consistent with angle resolved photoemission scattering. [Preview Abstract] |
Monday, March 2, 2015 10:00AM - 10:12AM |
A11.00011: Vortices and charge order in high-$T_{c}$ superconductors Matthias Einenkel, Hendrik Meier, Catherine P\'epin, Konstantin B. Efetov We theoretically investigate the vortex state of the cuprate high-temperature superconductors in the presence of magnetic fields. Assuming the recently derived nonlinear $\sigma$-model for fluctuations in the pseudogap phase, we find that the vortex cores consist of two crossed regions of elliptic shape, in which a static charge order emerges. Charge density wave order manifests itself as satellites to the ordinary Bragg peaks directed along the axes of the reciprocal copper lattice. Quadrupole density wave (bond order) satellites, if seen, are predicted to be along the diagonals. The intensity of the satellites should grow linearly with the magnetic field, in agreement with the result of recent experiments. [Preview Abstract] |
Monday, March 2, 2015 10:12AM - 10:24AM |
A11.00012: Orbital symmetry of charge density wave order in La$_{1.875}$Ba$_{0.125}$CuO$_4$ and YBa$_2$Cu$_3$O$_{6.67}$ David Hawthorn, Andrew Achkar, Feizhou He, Ronny Sutarto, Christopher McMahon, Martin Zwiebler, Markus H\"{u}cker, Genda Gu, Ruixing Liang, Doug Bonn, Walter Hardy, Jochen Geck Recent theories of charge density wave (CDW) order in high temperature superconductors have predicted a primarily $d$ CDW orbital symmetry. Here, we report on the orbital symmetry of CDW order in the canonical cuprate superconductors La$_{1.875}$Ba$_{0.125}$CuO$_4$ (LBCO) and YBa$_2$Cu$_3$O$_{6.67}$ (YBCO), using resonant soft x-ray scattering and a model mapped to the CDW orbital symmetry. From measurements sensitive to the O sublattice, we conclude that LBCO has predominantly $s'$ CDW orbital symmetry, in contrast to the $d$ orbital symmetry recently reported in other cuprates. Additionally, we find that the C$_4$ orbital symmetry of the Cu sublattice scattering is approximately preserved in LBCO and broken in YBCO. This work highlights orbital symmetry as an additional key property of CDW order that distinguishes the different cuprate families. We discuss how the CDW symmetry may be related to the ``1/8--anomaly'' and to static spin ordering. [Preview Abstract] |
Monday, March 2, 2015 10:24AM - 10:36AM |
A11.00013: Origin of Variety of Low-Energy ``Competing'' States Including d-form Factor Density Waves in Cuprates Wei-Lin Tu, Ting-Kuo Lee One of the most puzzling facts about the cuprate high temperature superconductors is the observation of a variety of low-energy states in coexistence with the superocnductivity and/or antiferromagnetism in the underdoped regime. These states could have a unidirectional charge density wave like structure or a bidirectional checkerboard structure. Some of them like the stripe state could also have an intertwined charge density and spin density waves together. Can all these different states caused by different mechanisms and competing with the superconducting state? Can these states also be consistent with the recently observed d-form factor density wave in cuprates? In this talk we will present reasons to show that these states are all orginated from the same strong correlation inherent in the cuprates. [Preview Abstract] |
Monday, March 2, 2015 10:36AM - 10:48AM |
A11.00014: Spin-Fluctuation-Driven Nematic Charge-Density-Wave in Cuprate Superconductors: Charge-Orbital-Spin Multimode Fluctuations Caused by Vertex Corrections Youichi Yamakawa, Masahisa Tsuchiizu, Hiroshi Kontani We explain the recently discovered nematic charge-density-wave (CDW) state in cuprate superconductors on the basis of the three-orbital $d$-$p$ Hubbard model, by including the vertex correction (VC) [1]. Due to the strong charge-spin interference given by the VC, the CDW instability at $q=(\Delta_{\rm FS},0)$, $(0,\Delta_{\rm FS})$ is strongly promoted near the magnetic critical point. Here, $\Delta_{\rm FS}$ is the wavenumber connected by the neighboring hot spots. The obtained spin-fluctuation-driven CDW is described as the ``intra-unit-cell orbital order'' accompanied by the charge transfer between the neighboring atomic orbitals. The obtained nematic-type charge pattern is similar to the STM results. The CDW in cuprates has a close relation to the nematic orbital order in Fe-based superconductors. [1] Y. Yamakawa and H. Kontani, arXiv:1406.7520. [Preview Abstract] |
(Author Not Attending)
|
A11.00015: Charge Order Instability in Doped Resonating Valence Bond State and Magnetic Orbits from Reconstructed Fermi Surface in Underdoped Cuprates Long Zhang, Jia-Wei Mei Recent experiments reveal incommensurate charge density wave (CDW) and quantum oscillations (QO) in the pseudogap phase of underdoped cuprates. In this work, we take a phenomenological synthesis of the resonating valence bond (RVB) state and the CDW order. Starting from the Yang-Rice-Zhang (YRZ) ansatz for the Green's function of the RVB state, we show that the CDW instability at wavevectors connecting the tips of the Fermi arcs can induce Fermi surface reconstruction. We find three primary magnetic orbits in the QO spectrum, the CDW-induced electron-like $\alpha$ and hole-like $\beta$ orbits and the $\gamma$ orbit enclosing the initial nodal YRZ hole pockets due to magnetic breakdown. Their combinations naturally explain the multi-component QO pattern observed in experiments. The $\gamma$ orbit encloses an area satisfying the generalized Luttinger theorem. The cyclotron mass of the $\gamma$ orbit increases monotonically with doping in agreement with the optical Hall angle measurements , while that of the $\alpha$ orbit is enhanced as the CDW order vanishes on approaching two critical dopings. However, we find that the enhancement of $m_{H}^{\alpha}$ is overestimated in QO experiments due to the ignorance of the impact of the CDW order suppression with increasing temperature. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700