Institution
Australian National University
Education•Canberra, Australian Capital Territory, Australia•
About: Australian National University is a education organization based out in Canberra, Australian Capital Territory, Australia. It is known for research contribution in the topics: Population & Galaxy. The organization has 34419 authors who have published 109261 publications receiving 4315448 citations. The organization is also known as: The Australian National University & ANU.
Topics: Population, Galaxy, Stars, Zircon, Politics
Papers published on a yearly basis
Papers
More filters
••
TL;DR: It is demonstrated that non-Hermiticity dramatically modifies the structure of modes and spectral degeneracies in exciton-polariton systems, and, therefore, will affect their quantum transport, localization and dynamical properties.
Abstract: Exciton-polaritons are hybrid light-matter quasiparticles formed by strongly interacting photons and excitons (electron-hole pairs) in semiconductor microcavities. They have emerged as a robust solid-state platform for next-generation optoelectronic applications as well as for fundamental studies of quantum many-body physics. Importantly, exciton-polaritons are a profoundly open (that is, non-Hermitian) quantum system, which requires constant pumping of energy and continuously decays, releasing coherent radiation. Thus, the exciton-polaritons always exist in a balanced potential landscape of gain and loss. However, the inherent non-Hermitian nature of this potential has so far been largely ignored in exciton-polariton physics. Here we demonstrate that non-Hermiticity dramatically modifies the structure of modes and spectral degeneracies in exciton-polariton systems, and, therefore, will affect their quantum transport, localization and dynamical properties. Using a spatially structured optical pump, we create a chaotic exciton-polariton billiard--a two-dimensional area enclosed by a curved potential barrier. Eigenmodes of this billiard exhibit multiple non-Hermitian spectral degeneracies, known as exceptional points. Such points can cause remarkable wave phenomena, such as unidirectional transport, anomalous lasing/absorption and chiral modes. By varying parameters of the billiard, we observe crossing and anti-crossing of energy levels and reveal the non-trivial topological modal structure exclusive to non-Hermitian systems. We also observe mode switching and a topological Berry phase for a parameter loop encircling the exceptional point. Our findings pave the way to studies of non-Hermitian quantum dynamics of exciton-polaritons, which may uncover novel operating principles for polariton-based devices.
498 citations
••
TL;DR: Findings from a exploratory study conducted with government officials in Arlington, VA between June and December 2010 are presented, with the broad goal of understanding social media use by government officials as well as community organizations, businesses, and the public at large.
497 citations
••
Leibniz Institute for Astrophysics Potsdam1, University of Ljubljana2, Lund University3, Australian National University4, University of Padua5, Centre national de la recherche scientifique6, Johns Hopkins University7, Heidelberg University8, Diego Portales University9, University of Cambridge10, University of Strasbourg11, University of Hull12, University of Victoria13, University College London14, Australian Astronomical Observatory15, Macquarie University16, University of Sydney17, University of Hong Kong18, Princeton University19, Columbia University20, Max Planck Society21, University of Birmingham22, Aarhus University23, Pierre-and-Marie-Curie University24
TL;DR: In this article, the stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity), radial velocities, individual abundances, and distances determined for 425,561 stars, which constitute the fourth public data release of the RAdial Velocity Experiment (RAVE).
Abstract: We present the stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity), radial velocities, individual abundances, and distances determined for 425,561 stars, which constitute the fourth public data release of the RAdial Velocity Experiment (RAVE). The stellar atmospheric parameters are computed using a new pipeline, based on the algorithms of MATISSE and DEGAS. The spectral degeneracies and the Two Micron All Sky Survey photometric information are now better taken into consideration, improving the parameter determination compared to the previous RAVE data releases. The individual abundances for six elements (magnesium, aluminum, silicon, titanium, iron, and nickel) are also given, based on a special-purpose pipeline that is also improved compared to that available for the RAVE DR3 and Chemical DR1 data releases. Together with photometric information and proper motions, these data can be retrieved from the RAVE collaboration Web site and the Vizier database.
497 citations
••
TL;DR: In this article, a preliminary attempt to work out what a nonfunctionalist social theory which still retains the crucial element of determination would look like is made, and the paper is arranged in th...
Abstract: This paper is a preliminary attempt to work out what a nonfunctionalist social theory which still retains the crucial element of determination would look like. The paper is therefore arranged in th...
497 citations
••
TL;DR: This work reviews evolutionary explanations for the relationship between anisogamy, potential reproductive rates, parental care, sex roles, and mate choice, and considers other forms of selection that can make females mate nonrandomly.
Abstract: Sexual reproduction is associated with the evolution of anisogamy and sperm-producing males and egg-laying females. The ensuing competition for mates has led to sexual selection and coevolution of the sexes. Mathematical models are extensively used to test the plausibility of different complicated scenarios for the evolution of sexual traits. Unfortunately, the diversity of models is now itself equally bewildering. Here we clarify some of the current debate by reviewing evolutionary explanations for the relationship between anisogamy, potential reproductive rates, parental care, sex roles, and mate choice. We review the benefits females might gain by mating with certain males rather than others. We also consider other forms of selection that can make females mate nonrandomly. One way empiricists can contribute to resolving theoretical disputes is to quantify the cost of expressing mating biases in the appropriate life-history currency.
495 citations
Authors
Showing all 34925 results
Name | H-index | Papers | Citations |
---|---|---|---|
Cyrus Cooper | 204 | 1869 | 206782 |
Nicholas G. Martin | 192 | 1770 | 161952 |
David R. Williams | 178 | 2034 | 138789 |
Krzysztof Matyjaszewski | 169 | 1431 | 128585 |
Anton M. Koekemoer | 168 | 1127 | 106796 |
Robert G. Webster | 158 | 843 | 90776 |
Ashok Kumar | 151 | 5654 | 164086 |
Andrew White | 149 | 1494 | 113874 |
Bernhard Schölkopf | 148 | 1092 | 149492 |
Paul Mitchell | 146 | 1378 | 95659 |
Liming Dai | 141 | 781 | 82937 |
Thomas J. Smith | 140 | 1775 | 113919 |
Michael J. Keating | 140 | 1169 | 76353 |
Joss Bland-Hawthorn | 136 | 1114 | 77593 |
Harold A. Mooney | 135 | 450 | 100404 |