Topological Monomodes in non-Hermitian Systems

Topological monomodes have been for long as elusive as magnetic monopoles. The latter was experimentally shown to emerge in effective descriptions of condensed-matter systems, while the experimental exploration of the former has largely been hindered by the complexity of the conceived setups. Here, we present a remarkably simple model and the experimental observation of topological monomodes generated dynamically. By focusing on non-Hermitian one-dimensional (1D) and 2D Su-Schrieffer-Heeger (SSH) models, we theoretically unveil the minimal configuration to realize a topological monomode upon engineering losses and breaking of lattice symmetries. Furthermore, we classify the systems in terms of the (non-Hermitian) symmetries that are present and calculate the corresponding topological invariants. To corroborate the theory, we present experiments in photonic lattices, in which a monomode is observed in the non-Hermitian 1D and 2D SSH models, thus breaking the paradigm that topological corner states should appear in pairs. Our findings might have profound implications for photonics and quantum optics because topological monomodes increase the robustness of corner states by preventing recombination.Comment: 30 (13+17) pages, 17 (4+13) figures, comments are welcom

Topological edge and corner states in Bi fractals on InSb

Topological materials hosting metallic edges characterized by integer quantized conductivity in an insulating bulk have revolutionized our understanding of transport in matter. The topological protection of these edge states is based on symmetries and dimensionality. However, only integer-dimensional models have been classified, and the interplay of topology and fractals, which may have a non-integer dimension, remained largely unexplored. Quantum fractals have recently been engineered in metamaterials, but up to present no topological states were unveiled in fractals realized in real materials. Here, we show theoretically and experimentally that topological edge and corner modes arise in fractals formed upon depositing thin layers of bismuth on an indium antimonide substrate. Scanning tunneling microscopy reveals the appearance of (nearly) zero-energy modes at the corners of Sierpi\'nski triangles, as well as the formation of outer and inner edge modes at higher energies. Unexpectedly, a robust and sharp depleted mode appears at the outer and inner edges of the samples at negative bias voltages. The experimental findings are corroborated by theoretical calculations in the framework of a continuum muffin-tin and a lattice tight-binding model. The stability of the topological features to the introduction of a Rashba spin-orbit coupling and disorder is discussed. This work opens the perspective to novel electronics in real materials at non-integer dimensions with robust and protected topological states.Comment: Main manuscript 14 pages, supplementary material 34 page

Measuring attitude toward theistic faith : assessing the Astley-Francis Scale among Christian, Muslim and secular youth in England

Empirical research within the social scientific study of religion in general and within the psychology of religion in particular remains very conscious of the complex nature of its subject matter. Empirical research in this field needs to take cognisance of the many forms in which religion is expressed (say, Buddhism, Christianity, Hinduism, Islam, Judaism, and Sikhism) and the many facets within the forms (say, beliefs, behaviours and affiliation). Working in the 1970s, Francis (1978a; 1978b) advanced the view that the attitudinal dimension of religion offered a particularly fruitful basis for coordinating empirical enquiry into the correlates, antecedents and consequences of religiosity across the life span

Water bottle flipping physics

The water bottle flipping challenge consists of spinning a bottle, partially filled with water, and making it land upright. It is quite a striking phenomenon, since at first sight, it appears rather improbable that a tall rotating bottle could make such a stable landing. Here, we analyze the physics behind the water bottle flip, based on experiments and an analytical model that can be used in the classroom. Our measurements show that the angular velocity of the bottle decreases dramatically, enabling a nearly vertical descent and a successful landing. The reduced rotation is due to an increase in the moment of inertia, caused by the in-flight redistribution of the water mass along the bottle. Experimental and analytical results are compared quantitatively, and we demonstrate how to optimize the chances for a successful landing.</p

Differences in early developmental rate and yolk conversion efficiency in offspring of trout with alternative life histories

Partial migration, in which some individuals of a population migrate while other individuals remain resident, is generally associated with ontogenetic shifts to better feeding areas or as a response to environmental instability, but its underlying mechanisms remain relatively unknown. Brown trout (Salmo trutta) exhibit partial migration, with some individuals remaining in fresh water (freshwater-resident) while others undertake an anadromous migration, where they spend time at sea before returning to breed in fresh water (migrant). We reared full-sibling groups of offspring from freshwater-resident and anadromous brown trout from the same catchment in the laboratory under common garden conditions to examine potential differences in their early development. Freshwater-resident parents produced eggs that were slower to hatch than those of anadromous parents, but freshwater-resident offspring were quicker to absorb their yolk and reach the stage of exogenous feeding. Their offspring also had a higher conversion efficiency from the egg stage to the start of exogenous feeding (so were larger by the start of the fry stage) than did offspring from anadromous parents despite no difference in standard metabolic rate, maximal metabolic rate, or aerobic scope. Given these differences in early development we discuss how the migration history of the parents might influence the migration probability of the offspring

Topological Monomodes in non-Hermitian Systems

Topological monomodes have been for long as elusive as magnetic monopoles. The latter was experimentally shown to emerge in effective descriptions of condensed-matter systems, while the experimental exploration of the former has largely been hindered by the complexity of the conceived setups. Here, we present a remarkably simple model and the experimental observation of topological monomodes generated dynamically. By focusing on non-Hermitian one-dimensional (1D) and 2D Su-Schrieffer-Heeger (SSH) models, we theoretically unveil the minimal configuration to realize a topological monomode upon engineering losses and breaking of lattice symmetries. Furthermore, we classify the systems in terms of the (non-Hermitian) symmetries that are present and calculate the corresponding topological invariants. To corroborate the theory, we present experiments in photonic lattices, in which a monomode is observed in the non-Hermitian 1D and 2D SSH models, thus breaking the paradigm that topological corner states should appear in pairs. Our findings might have profound implications for photonics and quantum optics because topological monomodes increase the robustness of corner states by preventing recombination

The Williams Scale of Attitude toward Paganism: development and application among British Pagans

This article builds on the tradition of attitudinal measures of religiosity established by Leslie Francis and colleagues with the Francis Scale of Attitude toward Christianity (and reflected in the Sahin-Francis Scale of Attitude toward Islam, the Katz-Francis Scale of Attitude toward Judaism, and the Santosh-Francis Scale of Attitude toward Hinduism) by introducing a new measure to assess the attitudinal disposition of Pagans. A battery of items was completed by 75 members of a Pagan Summer Camp. These items were reduced to produce a 21-item scale that measured aspects of Paganism concerned with: the God/Goddess, worshipping, prayer, and coven. The scale recorded an alpha coefficient of 0.93. Construct validity of the Williams Scale of Attitude toward Paganism was demonstrated by the clear association with measures of participation in private rituals

Durable response with single-agent acalabrutinib in patients with relapsed or refractory mantle cell lymphoma

Bruton tyrosine kinase (BTK) inhibitors have greatly improved the spectrum of treatment options in mantle cell lymphoma (MCL) [1–4]. Acalabrutinib is a highly selective, orally administered, and potent BTK inhibitor with limited off-target activity [5]. Acalabrutinib was approved in 2017 by the US Food and Drug Administration for the treatment of relapsed/refractory MCL based on clinical data from the open-label, multicenter, phase 2 ACE-LY-004 study of acalabrutinib 100 mg twice daily [1]. Here, we present updated results from the ACE-LY-004 study after a median 26-month follow-up. Eligibility criteria and study design were published previously (Supplementary methods) [1]. Analysis of minimal residual disease (MRD) was conducted after complete response (CR) or partial response (PR) was achieved using the quantitative ClonoSEQ next-generation sequencing (5 × 10−6 ) assay (Adpative Biotechnologies, Seattle, WA, USA) in consenting patients with available paired archival tumor and whole blood samples. Data are updated as of February 12, 2018