Switched wave packets: A route to nonperturbative quantum control

The dynamic Stark effect due to a strong nonresonant but nonionizing laser field provides a route to quantum control via the creation of novel superposition states. We consider the creation of a field-free "switched" wave packet through adiabatic turn-on and sudden turn-off of a strong dynamic Stark interaction. There are two limiting cases for such wave packets. The first is a Raman-type coupling, illustrated by the creation of field-free molecular axis alignment. An experimental demonstration is given. The second case is that of dipole-type coupling, illustrated by the creation of charge localization in an array of quantum wells

Are you talking to me? An analysis of journalism conversation on social media

Social media has become a key medium for discussion and dissemination of news stories, fuelled by the low barrier to entry and the ease of interaction. News stories may be propagated through these networks either by official news organisation accounts, by individual journalists or by members of the public, through link sharing, endorsing or commenting. This preliminary research aims to show how computational analysis of large-scale data-sets allows us to investigate the means by which news stories are spread through social media, and how the conversation around them is shaped by journalists and news organisations. Through the capture of more than 11 million tweets relating to 2303 Twitter accounts connected to journalism and news organisations, we are able to analyse the conversation within and around journalism, examining who spreads information about news articles and who interacts in the discussion around them. Capturing the tweets of news organisations and journalists and the replies and retweets of these micro-blogs allows us to build a rich picture of interaction around news media

Piezomorphic materials

The development of stress-induced morphing materials which are described as piezomorphic materials is reported. The development of a piezomorphic material is achieved by introducing spatial dependency into the compliance matrix describing the elastic response of a material capable of undergoing large strain deformation. In other words, it is necessary to produce an elastically gradient material. This is achieved through modification of the microstructure of the compliant material to display gradient topology. Examples of polymeric (polyurethane) foam and microporous polymer (expanded polytetrafluoroethylene) piezomorphic materials are presented here. These materials open up new morphing applications where dramatic shape changes can be triggered by mechanical stress

Reconstructing boulder deposition histories: extreme wave signatures on a complex rocky shoreline of Malta

The Żonqor coastline, southeast Malta, displays an exceptional range of geomorphic signatures of extreme coastal events. This paper brings together evidence acquired from a field survey, analysis of time-sequential imagery, and hydrodynamic modelling to investigate the histories of boulder groups identified by their intrinsic and contextual characteristics. Clear differences are revealed between the distribution of boulders recently moved and those of considerable age. Tracking the movement of boulders since 1957 confirms that storms of surprisingly frequent interval are capable of complex boulder movements, including lifting of megaclasts. Scrutiny of the ancient boulders, including weathering features and fascinating landward-facing (reverse) imbrication, cautiously suggests tsunami as the agent for their emplacement. A novel method is developed for depicting the velocity decay profiles of hypothetical waves, which overcomes some of the limitations of the Nott approach. Applied here, the wave run-up context further sets the ancient movers apart from their recent mover companions. The combined evidence implies a palimpsestic landscape where storm waves are regular geomorphic agents that add to and rework the distribution of boulders close to the shoreline, but over long time periods the landscape becomes reset by tsunami—a concept that is of value to agencies in Malta responsible for coastal safety, planning and management

‘Racist behaviour is interfering with the game’: exploring football fans’ online responses to accusations of racism in football

This paper explores an incident of alleged fan racism involving Chelsea defender, Antonio Rüdiger. During a match against Tottenham Hotspur, in December 2019, Rüdiger claimed he heard racial abuse from Spurs fans. This incident sparked a broader national conversation regarding racism in sport, and wider society. This paper will draw on a comprehensive content analysis of Twitter comments to provide insights into fan reactions at the time of the incident. Was Rüdiger alleged to have played the ‘race card’? Was Rüdiger believed to have used his ‘race’ to attempt to punish the Spurs’ fans? Using thematic analysis, it will highlight patterns in fan responses to this case and attempt to illustrate football fans’ attitudes towards ‘race’ and racism within English football. The paper will close by offering some final thoughts on how racism, and other forms of discrimination, can be both challenged inside the stadium and on social media

Fermi Surface and Quasiparticle Excitations of overdoped Tl2Ba2CuO6+d by ARPES

The electronic structure of the high-T_c superconductor Tl2Ba2CuO6+d is studied by ARPES. For a very overdoped Tc=30K sample, the Fermi surface consists of a single large hole pocket centered at (pi,pi) and is approaching a topological transition. Although a superconducting gap with d_x^2-y^2 symmetry is tentatively identified, the quasiparticle evolution with momentum and binding energy exhibits a marked departure from the behavior observed in under and optimally doped cuprates. The relevance of these findings to scattering, many-body, and quantum-critical phenomena is discussed.Comment: Revised manuscript, in press on PRL. A high-resolution version can be found at http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Articles/Tl2201_LE.pdf and related material at http://www.physics.ubc.ca/~quantmat/ARPES/PUBLICATIONS/articles.htm

Investigating Online Fan Responses to the Rooney Rule in English Football

Purpose This work critically investigates online fan responses towards the implementation of the affirmative action policy, the Rooney Rule, within English professional football. It explores systemic and structural racism and the history of the Rooney Rule, before analysing football fans' Twitter comments concerning the policy within English football across an 18-month period. Design/methodology/approach This research utilised a bespoke search programme to identify and analyse Tweets which focused on the Rooney Rule in English football. A total of 205 posts were thematically analysed and a series of codes were created. Findings The findings illustrated that fans were generally divided over the Rooney Rule. Over half of the participants welcomed counter measures against structural racism although many caveated responses by critiquing the Rule's approach and scope. For others, however, the policy is yet another example of ‘reverse racism’ and ‘political correctness gone mad’. The findings illustrate that there is an undercurrent of hostility towards anti-racist action and a belief that sport is inherently meritocratic and fair. Originality/value While much research has focused on examining online reactions to ‘trigger events’, this chapter provides an empirical insight into contemporary football fan responses towards anti-racist action in the ‘beautiful game’. It demonstrates that there are a series of common misconceptions and misunderstandings towards affirmative action policies in sport. Once we become aware of such misunderstandings, we can attempt to remedy them in order to aid the efficacy of anti-racist action