Plusiotis ericsmithi (Coleoptera: Scarabaeidae) : a new metallic species from eastern Guatemala

Se describe Plusiotis ericsmithi sp. nov. de un bosque nuboso de baja altitud (1100 msnm) en la Sierra del Merend6n, Guatemala, cerca de la front era con Honduras. Ademas, se incluyen ilustraciones de los genitales masculinos y femeninos.Plusiotis ericsmithii n. sp. is described from a low altitude cloud forest (1100 m) in the Guatemalan Merend6n mountain chain near the Honduran border. Male and female genitalia are illustrated

Quantum spin models for the SU(n)_1 Wess-Zumino-Witten model

We propose 1D and 2D lattice wave functions constructed from the SU(n)_1 Wess-Zumino-Witten (WZW) model and derive their parent Hamiltonians. When all spins in the lattice transform under SU(n) fundamental representations, we obtain a two-body Hamiltonian in 1D, including the SU(n) Haldane-Shastry model as a special case. In 2D, we show that the wave function converges to a class of Halperin's multilayer fractional quantum Hall states and belongs to chiral spin liquids. Our result reveals a hidden SU(n) symmetry for this class of Halperin states. When the spins sit on bipartite lattices with alternating fundamental and conjugate representations, we provide numerical evidence that the state in 1D exhibits quantum criticality deviating from the expected behaviors of the SU(n)_1 WZW model, while in 2D they are chiral spin liquids being consistent with the prediction of the SU(n)_1 WZW model.Comment: 28 pages, 9 figures, published versio

Notes on Guatemalan Plusiotis (Coleoptera: Scarabaeidae; Rutelinae)

Dos especies nuevas de escarabajos del genero Plusiotis se describen de un bosque nuboso, 1560-1900 m en el departamento de San Marcos, Guatemala. Tambien se describen las hembras de P. turhheimi Ohaus, P. auropunctata Ohaus y P. quiche Moron. Ademas, se registra pOI' primera vez a P. turhheimi para Guatemala.Two new species of Plusiotis are described from a cloud forest between 1560-1900 m in the Department of San Marcos, Guatemala. Females of P. turhheimi Ohaus, P. auropunctata Ohaus and P. quiche Moron are described. Plusiotis turhheimi is reported from Guatemala for the first time

Optical lattice implementation scheme of a bosonic topological model with fermionic atoms

We present a scheme to implement a Fermi-Hubbard-like model in ultracold atoms in optical lattices and analyze the topological features of its ground state. In particular, we show that the ground state for appropriate parameters has a large overlap with a lattice version of the bosonic Laughlin state at filling factor one half. The scheme utilizes laser assisted and normal tunnelling in a checkerboard optical lattice. The requirements on temperature, interactions, and hopping strengths are similar to those needed to observe the N\'eel antiferromagnetic ordering in the standard Fermi-Hubbard model in the Mott insulating regime.Comment: 18 pages, 10 figures. This article provides the full analysis of a scheme proposed in Nat. Commun. 4, 2864 (2013). v2: accepted versio

Construction of spin models displaying quantum criticality from quantum field theory

We provide a method for constructing finite temperature states of one-dimensional spin chains displaying quantum criticality. These models are constructed using correlators of products of quantum fields and have an analytical purification. Their properties can be investigated by Monte-Carlo simulations, which enable us to study the low-temperature phase diagram and to show that it displays a region of quantum criticality. The mixed states obtained are shown to be close to the thermal state of a simple nearest neighbour Hamiltonian.Comment: 10 pages, 6 figure

Bosonic Gaussian states from conformal field theory

We study nonchiral wave functions for systems with continuous spins obtained from the conformal field theory (CFT) of a free, massless boson. In contrast to the case of discrete spins, these can be treated as bosonic Gaussian states, which allows us to efficiently compute correlations and entanglement properties both in one (1D) and in two spatial dimensions (2D). In 1D, the computed entanglement entropy and spectra are in agreement with the underlying CFT. Furthermore, we construct a 1D parent Hamiltonian with a low-energy spectrum corresponding to that of a free, massless boson. In 2D, we find edge excitations in the entanglement spectrum, although the states do not have intrinsic topological order, as revealed by a determination of the topological entanglement entropy.Comment: 18 pages, 8 figures, v2: accepted versio

Lattice effects on Laughlin wave functions and parent Hamiltonians

We investigate lattice effects on wave functions that are lattice analogues of bosonic and fermionic Laughlin wave functions with number of particles per flux $\nu=1/q$ in the Landau levels. These wave functions are defined analytically on lattices with $\mu$ particles per lattice site, where $\mu$ may be different than $\nu$. We give numerical evidence that these states have the same topological properties as the corresponding continuum Laughlin states for different values of $q$ and for different fillings $\mu$. These states define, in particular, particle-hole symmetric lattice Fractional Quantum Hall states when the lattice is half-filled. On the square lattice it is observed that for $q\leq 4$ this particle-hole symmetric state displays the topological properties of the continuum Laughlin state at filling fraction $\nu=1/q$, while for larger $q$ there is a transition towards long-range ordered anti-ferromagnets. This effect does not persist if the lattice is deformed from a square to a triangular lattice, or on the Kagome lattice, in which case the topological properties of the state are recovered. We then show that changing the number of particles while keeping the expression of these wave functions identical gives rise to edge states that have the same correlations in the bulk as the reference lattice Laughlin states but a different density at the edge. We derive an exact parent Hamiltonian for which all these edge states are ground states with different number of particles. In addition this Hamiltonian admits the reference lattice Laughlin state as its unique ground state of filling factor $1/q$. Parent Hamiltonians are also derived for the lattice Laughlin states at other fillings of the lattice, when $\mu\leq 1/q$ or $\mu\geq 1-1/q$ and when $q=4$ also at half-filling.Comment: 18 pages, 15 figure