Quantum fluids of light in all-optical scatterer lattices

AbstractOne of the recently established paradigms in condensed matter physics is examining a system’s behaviour in artificial potentials, giving insight into phenomena of quantum fluids in hard-to-reach settings. A prominent example is the matter-wave scatterer lattice, where high energy matter waves undergo transmission and reflection through narrow width barriers leading to stringent phase matching conditions with lattice band formation. In contrast to evanescently coupled lattice sites, the realisation of a scatterer lattice for macroscopic matter-wave fluids has remained elusive. Here, we implement a system of exciton-polariton condensates in a non-Hermitian Lieb lattice of scatterer potentials. By fine tuning the lattice parameters, we reveal a nonequilibrium phase transition between distinct regimes of polariton condensation: a scatterer lattice of gain guided polaritons condensing on the lattice potential maxima, and trapped polaritons condensing in the potential minima. Our results pave the way towards unexplored physics of non-Hermitian fluids in non-stationary mixtures of confined and freely expanding waves.

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Exploring Flaring Behaviour on Low Mass Stars, Solar-type Stars and the Sun

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319009980 ◽

2019 ◽

Vol 15 (S354) ◽

pp. 384-391

Author(s):

L. Doyle ◽

G. Ramsay ◽

J. G. Doyle ◽

P. F. Wyper ◽

E. Scullion ◽

...

Keyword(s):

High Energy ◽

The Sun ◽

Low Mass Stars ◽

Highly Active ◽

Rotation Phase ◽

Solar Type ◽

Low Mass ◽

Insight Into ◽

Reconnection Model ◽

High Cadence

AbstractWe report on our project to study the activity in both the Sun and low mass stars. Utilising high cadence, Hα observations of a filament eruption made using the CRISP spectropolarimeter mounted on the Swedish Solar Telescope has allowed us to determine 3D velocity maps of the event. To gain insight into the physical mechanism which drives the event we have qualitatively compared our observation to a 3D MHD reconnection model. Solar-type and low mass stars can be highly active producing flares with energies exceeding erg. Using K2 and TESS data we find no correlation between the number of flares and the rotation phase which is surprising. Our solar flare model can be used to aid our understanding of the origin of flares in other stars. By scaling up our solar model to replicate observed stellar flare energies, we investigate the conditions needed for such high energy flares.

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CRITICAL PHENOMENA IN DEEP INELASTIC SCATTERING

International Journal of Modern Physics A ◽

10.1142/s0217751x10051104 ◽

2010 ◽

Vol 25 (31) ◽

pp. 5667-5682 ◽

Cited By ~ 6

Author(s):

L. L. JENKOVSZKY ◽

ANDREA NAGY ◽

S. M. TROSHIN ◽

JOLÁN TURÓCI ◽

N. E. TYURIN

Keyword(s):

Phase Transition ◽

Inelastic Scattering ◽

Deep Inelastic Scattering ◽

Deeply Virtual Compton Scattering ◽

Virtual Compton Scattering ◽

Heavy Ion ◽

High Energy ◽

Ion Collisions ◽

Bjorken X ◽

Insight Into

Saturation in deep inelastic scattering and deeply virtual Compton scattering is associated with a phase transition between the partonic gas, typical of moderate x and Q2, and partonic fluid appearing at increasing Q2 and decreasing Bjorken x. In this paper we do not intend to propose another parametrization of the structure function; instead we suggest a new insight into the internal structure of the nucleon, as seen in deep inelastic scattering, and its connection with that revealed in high-energy nucleons and heavy-ion collisions.

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Fine-Tuning the Carbon - Electrolyte Interface for Designing High Energy Density Double Layer Capacitors

ECS Meeting Abstracts ◽

10.1149/ma2012-02/6/504 ◽

2012 ◽

Keyword(s):

Energy Density ◽

Double Layer ◽

High Energy ◽

Fine Tuning ◽

High Energy Density ◽

Electrolyte Interface ◽

Double Layer Capacitors

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Future searches for free and bound n → n̅ transformations

EPJ Web of Conferences ◽

10.1051/epjconf/201921907005 ◽

2019 ◽

Vol 219 ◽

pp. 07005 ◽

Cited By ~ 1

Author(s):

Albert Young ◽

Joshua Barrow

Keyword(s):

High Energy Physics ◽

Complex Dynamics ◽

Rare Event ◽

Baryon Number ◽

High Energy ◽

Big Bang ◽

Fine Tuning ◽

Transformation Rate ◽

Baryon Number Violation ◽

The Big Bang

Baryon number violation, a key, non-perturbative prediction of the Standard Model (SM) via electroweak instantons (sphalerons), has never been definitively observed. However, its relationship to baryogenesis is obscure, and, within the context of the SM, seems to require fine tuning and complex dynamics to occur mere instants after the chaos of the Big Bang began. Post-sphaleron baryogenesis (PSB), a SM extension first proposed by Babu et al. in 2006, seems to compellingly quell many of these theoretical conundrums while effectively predicting the baryon abundance, and simultaneously offering a tantalizing experimental observable: neutron–antineutron transformations (n → n̅). This rare event, a phenomena similar to meson oscillations, can be thought of as a form of dinucleon decay, and is hypothesized to occur for both the free and bound neutron; what's more, within the context of PSB, there exits an upper limit on the free neutron transformation rate. The subject of the relatedness of the free and bound rates promises a wealth of exciting nuclear and high-energy physics, and the complimentary nature of both types of experimental searches argues for their mutual necessity. In this paper, we briefly discuss the physics of the transformation, and our groups' plans to search for this critically important phenomena using both the free and bound neutron.

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A bottom-up approach to fermion mass hierarchy: a case with vector-like fermions

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptaa046 ◽

2020 ◽

Vol 2020 (4) ◽

Cited By ~ 1

Author(s):

Yoshiharu Kawamura

Keyword(s):

Standard Model ◽

Yukawa Coupling ◽

High Energy ◽

Fine Tuning ◽

Fermion Mass ◽

Extended Model ◽

Mass Hierarchy ◽

Bottom Up ◽

Existence Proofs ◽

The Standard Model

Abstract We propose a bottom-up approach in which a structure of high-energy physics is explored by accumulating existence proofs and/or no-go theorems in the standard model or its extension. As an illustration, we study fermion mass hierarchies based on an extension of the standard model with vector-like fermions. It is shown that the magnitude of elements of Yukawa coupling matrices can become $O(1)$ and a Yukawa coupling unification can be realized in a theory beyond the extended model, if vector-like fermions mix with three families. In this case, small Yukawa couplings in the standard model can be highly sensitive to a small variation of matrix elements, and it seems that the mass hierarchy occurs as a result of fine tuning.

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Fine-tuning locational formulations in mobile phone calls

Discourse Studies ◽

10.1177/1461445620914674 ◽

2020 ◽

Vol 22 (5) ◽

pp. 553-570

Author(s):

Ali Kazemi

Keyword(s):

Mobile Phone ◽

Social Action ◽

Perspective Taking ◽

Physical Environment ◽

Fine Tuning ◽

Conversational Analysis ◽

Phone Calls ◽

Data Informed ◽

Insight Into ◽

Selection Of

This study examines the sequential and situated organization associated with framing locational formulations by dislocated parties to mobile phone calls for the joint accomplishment of location-related social action. The data come from 22 mundane Farsi mobile phone calls involving location inquiring and/or reporting. The analysis of the data, informed by conversational analysis and Levinson’s conceptual framework of perspective-taking, adds frame of reference (hereafter, FoR) to Schegloff’s location, membership, and topic or activity analyses operative in the selection of locational formulations. The trajectory plotted for location-related action indicates the contingent roles which material, linguistic and semiotic resources play in the selection of locational formulations deployed for co-presence purposes. The findings suggest consequentiality of the-relevant-next action for the framing of locational descriptions and provide insight into how conversationalists interact with their physical environment in a wider social context.

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New insight into understanding the susceptibility of digital avionics to high energy RF (HERF)

10.1109/dasc.1990.111319 ◽

2002 ◽

Author(s):

D. Sorensen ◽

G. Fuller

Keyword(s):

High Energy ◽

Insight Into

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The Influence of Repressor DNA Binding Site Architecture on Transcriptional Control

mBio ◽

10.1128/mbio.01684-14 ◽

2014 ◽

Vol 5 (5) ◽

Cited By ~ 11

Author(s):

Dan M. Park ◽

Patricia J. Kiley

Keyword(s):

Escherichia Coli ◽

Dna Binding ◽

Binding Site ◽

Information Content ◽

Fine Tuning ◽

Carbon Oxidation ◽

Content Type ◽

Architectural Features ◽

Recognition Elements ◽

Insight Into

ABSTRACTHow the architecture of DNA binding sites dictates the extent of repression of promoters is not well understood. Here, we addressed the importance of the number and information content of the three direct repeats (DRs) in the binding and repression of theicdApromoter by the phosphorylated form of the globalEscherichia colirepressor ArcA (ArcA-P). We show that decreasing the information content of the two sites with the highest information (DR1 and DR2) eliminated ArcA binding to all three DRs and ArcA repression oficdA. Unexpectedly, we also found that DR3 occupancy functions principally in repression, since mutation of this low-information-content site both eliminated DNA binding to DR3 and significantly weakenedicdArepression, despite the fact that binding to DR1 and DR2 was intact. In addition, increasing the information content of any one of the three DRs or addition of a fourth DR increased ArcA-dependent repression but perturbed signal-dependent regulation of repression. Thus, our data show that the information content and number of DR elements are critical architectural features for maintaining a balance between high-affinity binding and signal-dependent regulation oficdApromoter function in response to changes in ArcA-P levels. Optimization of such architectural features may be a common strategy to either dampen or enhance the sensitivity of DNA binding among the members of the large OmpR/PhoB family of regulators as well as other transcription factors.IMPORTANCEInEscherichia coli, the response regulator ArcA maintains homeostasis of redox carriers under O2-limiting conditions through a comprehensive repression of carbon oxidation pathways that require aerobic respiration to recycle redox carriers. Although a binding site architecture comprised of a variable number of sequence recognition elements has been identified within the promoter regions of ArcA-repressed operons, it is unclear how this variable architecture dictates transcriptional regulation. By dissecting the role of multiple sequence elements within theicdApromoter, we provide insight into the design principles that allow ArcA to repress transcription within diverse promoter contexts. Our data suggest that the arrangement of recognition elements is tailored to achieve sufficient repression of a given promoter while maintaining appropriate signal-dependent regulation of repression, providing insight into how diverse binding site architectures link changes in O2with the fine-tuning of carbon oxidation pathway levels.

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