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Replication data for: Topology with Memory in Nonlinear Driven-Dissipative Photonic Lattices
No full textData corresponding to all figures in .mat format
One-Way Reflection-Free Exciton-Polariton Spin-Filtering Channel
No full textWe consider theoretically exciton-polaritons in a strip of honeycomb lattice with zigzag edges and it is shown that the interplay among the spin-orbit coupling, Zeeman splitting, and an on-site detuning between sublattices can give rise to a band structure where all the edge states of the system split in energy. Within an energy interval, one of the spin-polarized edge states resides with the gapless bulk that has opposite spin. Being surrounded by opposite spin, and the absence of the backward-propagating edge state, ensures both reflection-free and feedback-suppressed one-way flow of polaritons with one particular spin in the system. The edge states in this system are more localized than those in the standard topological-polariton systems and are fully spin polarized. This paves the way for feedback-free spin-selective polariton channels for transferring information in polariton networks
Replication Data for: On the possibility of a terahertz light emitting diode based on a dressed quantum well
No full textWe consider theoretically the realization of a tunable terahertz light emitting diode from a quantum well with dressed electrons placed in a highly doped p-n junction. in the considered system the strong resonant dressing field forms dynamic Stark gaps in the valence and conduction bands and the electric field inside the p-n junction makes the QW asymmetric. It is shown that the electrons transiting through the light induced Stark gaps in the conduction band emit photons with energy directly proportional to the dressing field. This scheme is tunable, compact, and shows a fair efficiency
Replication Data for: Antichiral edge states in an exciton polariton strip
No full textWe present a scheme to obtain antichiral edge states in an exciton-polariton honeycomb lattice with strip geometry, where the modes corresponding to both edges propagate in the same direction. Under resonant pumping the effect of a polariton condensate with nonzero velocity in one linear polarization is predicted to tilt the dispersion of polaritons in the other, which results in an energy shift between two Dirac cones, and the otherwise flat edge states become tilted. Our simulations show that due to the spatial separation from the bulk modes the edge modes are robust against disorder
Dynamics of light-matter coupled quasiparticles
No full textOur world is made of light and matter. While light can travel very fast, it interacts very weakly. On the other hand, matter interacts very strongly but travels very slowly. The combination of light and matter can give rise to fascinating effects, which light or matter alone cannot show. Dressed electrons and exciton-polaritons are examples of such light-matter coupled systems where the matter is dressed by light to form new quasi-particles with unique properties.
In chapters 2 and 3 of the thesis, we investigate the dressed electrons inside a quantum well and predict that such a system can be used to generate terahertz (THz) waves. This is particularly interesting due to the absence of THz bandgaps in state-of-the-art QWs and it is only because of the dressing field that such a band gap opens up.
In chapters 4 and 5 of the thesis, we introduce schemes to obtain robust propagation of exciton-polaritons. Exciton-polaritons are predicted to play an important role in future optoelectronic devices. However, to realize complete devices, robust propagation of polaritons between different components is essential. We predict that the inherent nonlinear nature of the polaritons gives rise to antichiral edge states in a honeycomb lattice strip, where polaritons propagate robustly through both edges of the strip in the same direction. Next, using the naturally present spin-orbit coupling in the microcavity along with the external magnetic field, feedback-free robust propagation of polaritons with a particular spin is also predicted. These results are motivated by the recent advance of topological photonics, although we will focus on non-topological systems. We find that in some cases there are trade-offs between having non-trivial or trivial topology in which even topologically trivial systems can partially display desirable effects, more commonly associated with topological systems while having other advantages such as accessibility in light-matter coupled systems.Doctor of Philosoph
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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