We report results of largescale groundstate density matrix renormalization group (DMRG) calculations on t
In the physics of condensed matter, quantum critical phenomena and unconventional superconductivity are two major themes. In electrondoped cuprates, the low critical field (H_{C2}) allows one to study the putative quantum critical point (QCP) at low temperature and to understand its connection to the longstanding problem of the origin of the high
 Award ID(s):
 1708334
 Publication Date:
 NSFPAR ID:
 10087945
 Journal Name:
 Proceedings of the National Academy of Sciences
 Volume:
 116
 Issue:
 13
 Page Range or eLocationID:
 p. 59915994
 ISSN:
 00278424
 Publisher:
 Proceedings of the National Academy of Sciences
 Sponsoring Org:
 National Science Foundation
More Like this

${t}^{\prime}$ J cylinders with circumferences 6 and 8. We determine a rough phase diagram that appears to approximate the twodimensional (2D) system. While for many properties, positive and negative${t}^{\prime}$ values (${t}^{\prime}/t=\pm 0.2$ ) appear to correspond to electron and holedoped cuprate systems, respectively, the behavior of superconductivity itself shows an inconsistency between the model and the materials. The${t}^{\prime}<0$ (holedoped) region shows antiferromagnetism limited to very low doping, stripes more generally, and the familiar Fermi surface of the holedoped cuprates. However, we find${t}^{\prime}<0$ strongly suppresses superconductivity. The${t}^{\prime}>0$ (electrondoped) regionmore » 
SubNeptunes are common among the discovered exoplanets. However, lack of knowledge on the state of matter in
${\mathrm{H}}_{2}$ Orich setting at high pressures and temperatures ($PT$ ) places important limitations on our understanding of this planet type. We have conducted experiments for reactions between${\mathrm{S}\mathrm{i}\mathrm{O}}_{2}$ and${\mathrm{H}}_{2}$ O as archetypal materials for rock and ice, respectively, at high$PT$ . We found anomalously expanded volumes of dense silica (up to 4%) recovered from hydrothermal synthesis above ∼24 GPa where the${\mathrm{C}\mathrm{a}\mathrm{C}\mathrm{l}}_{2}$ type (Ct) structure appears at lower pressures than in the anhydrous system. Infrared spectroscopy identifiedmore » 
The Kohn–Sham potential
${v}_{\text{eff}}\left(\mathbf{r}\right)$ is the effective multiplicative operator in a noninteracting Schrödinger equation that reproduces the groundstate density of a real (interacting) system. The sizes and shapes of atoms, molecules, and solids can be defined in terms of Kohn–Sham potentials in a nonarbitrary way that accords with chemical intuition and can be implemented efficiently, permitting a natural pictorial representation for chemistry and condensedmatter physics. Let${\u03f5}_{\text{max}}$ be the maximum occupied orbital energy of the noninteracting electrons. Then the equation${v}_{\text{eff}}\left(\mathbf{r}\right)={\u03f5}_{\text{max}}$ defines the surface at which classical electrons with energy$\u03f5\le {\u03f5}_{\text{max}}$ would be turned back and thus determines the surface of anymore » 
We present exact results that give insight into how interactions lead to transport and superconductivity in a flat band where the electrons have no kinetic energy. We obtain bounds for the optical spectral weight for flatband superconductors that lead to upper bounds for the superfluid stiffness and the twodimensional (2D)
${T}_{c}$ . We focus on onsite attraction$\leftU\right$ on the Lieb lattice with trivial flat bands and on the πflux model with topological flat bands. For trivial flat bands, the lowenergy optical spectral weight${\stackrel{\u0303}{D}}_{\text{low}}\le \stackrel{\u0303}{n}\leftU\right\mathrm{\Omega}/2$ with$\stackrel{\u0303}{n}=min\left(n,2n\right)$ , where n is the flatband density and Ω is themore » 
Abstract Physical systems with nontrivial topological order find direct applications in metrology (Klitzing
et al 1980Phys .Rev. Lett .45 494–7) and promise future applications in quantum computing (Freedman 2001Found. Comput. Math. 1 183–204; Kitaev 2003Ann. Phys. 303 2–30). The quantum Hall effect derives from transverse conductance, quantized to unprecedented precision in accordance with the system’s topology (Laughlin 1981Phys. Rev. B23 5632–33). At magnetic fields beyond the reach of current condensed matter experiment, around T, this conductance remains precisely quantized with values based on the topological order (Thouless ${\mathrm{10}}^{\mathrm{4}}$et al 1982Phys. Rev. Lett. 49 405–8). Hitherto, quantized conductance has only been measured in extended 2D systems. Here, we experimentally studied narrow 2Dmore »