Surface waves at the interface between left-handed and birefringent materials

We theoretically investigate the existence and properties of hybrid surface waves forming at interfaces between left-handed materials and dielectric birefringent media. The existence conditions of such waves are found to be highly relaxed in comparison to the original hybrid surface waves, discovered by Dyakonov, in configurations involving birefringent materials and right-handed media. Hybrid surface waves in left-handed materials feature remarkable properties: (i) a high degree of localization and (ii) coexistence of several guided solutions. The existence of several hybrid surface waves for the same parameter set is linked to the birefringent nature of the medium whereas the strong localization is related to the presence of the left-handed material. The hybrid surface modes appear for large areas in the parameter space.Comment: 11 pages, 6 figure

Using interactive whiteboard in teaching biology

In recent years, with the rapid development of Information Communication Technology (ICT), integrating multimedia presentation tools to perform better teaching has become easier in today’s classroom. Among many ICT systems, the innovation and introduction of IWB has not only changed the traditional classroom but symbolizes a key revolution in the history of whiteboard development. Researchers have identified a number of advantages of using IWB in teaching and learning: flexibility and versatility, multimedia/multimodal presentation, improving teaching efficiency, supporting planning and the development of resources, improving students’ skills of using ICT technology, interactivity and participation during course, improving students’ learning motivation, and improving students’understanding. Following the trend of integrating IWB into teaching, this research tries to understand how to make good use of the advantages of IWB to make students have better learning effectiveness on junior high school Biology. The goal of this paper is to design interactive teaching strategies with Interactive WhiteBoard (IWB) and investigate their effectiveness on teaching biology

Observation of Dyakonov surface waves

We report the first experimental observation of Dyakonov surface waves existing at the interface of transparent anisotropic crystals. A Otto-Kretchmann configuration was used to excite the surface waves at the interface between a potassium titanyl phosphate biaxial crystal and an index-matching liquid fulfilling the conditions at which the waves exist. The signature of surface wave excitation was obtained by using enhanced polarization-conversion reflectance phenomena. We measured the cutoff propagation angles for different index-matching liquids, confirming the high sensitivity of the propagation conditions with the properties of the supporting interface.Peer Reviewe

Three-dimensional walking spatiotemporal solitons in quadratic media

Two-parameter families of chirped stationary three-dimensional spatiotemporal solitons in dispersive quadratically nonlinear optical media featuring type-I second-harmonic generation are constructed in the presence of temporal walk-off. Basic features of these walking spatiotemporal solitons, including their dynamical stability, are investigated in the general case of unequal group-velocity dispersions at the fundamental and second-harmonic frequencies. In the cases when the solitons are unstable, the growth rate of a dominant perturbation eigenmode is found as a function of the soliton wave number shift. The findings are in full agreement with the stability predictions made on the basis of a marginal linear-stability curve. It is found that the walking three-dimensional spatiotemporal solitons are dynamically stable in most cases; hence in principle they may be experimentally generated in quadratically nonlinear media.Peer ReviewedPostprint (published version

The Futures of Adult Educator(s): Agency, Identity and Ethos. Joint Conference Proceedings of the 2nd ESREA/ReNAdET Meeting and the 4th TQF Seminar (Tallinn, Estonia, November 9-11, 2011)

Heikkinen A, Jogi L, Jütte W, Zarifis GK. The Futures of Adult Educator(s): Agency, Identity and Ethos. Joint Conference Proceedings of the 2nd ESREA/ReNAdET Meeting and the 4th TQF Seminar (Tallinn, Estonia, November 9-11, 2011).; 2012.This edited volume contains the papers presented in the 2nd ESREAReNAdet} meeting that was jointly organised with the VET & CULTURE Network in the University of Tallinn (Estonia), 9-11 November 2011. The papers that appear in the volume discuss the future (or the futures) of adult educators in respect to issues of developing their identities and professional status, issues of networking and/or unionizing and collaborating among different "types" of adult educators and related staff in adult education in general, and issues of power and authority in the adult-educator interaction. The selected number of contributions that appear in the volume focus on following themes: (1) Perceptions of adult educators: by adults-students, policy makers and in public; (2) Theoretical, political and practical discourses on adult educators: the future of adult education as an academic field; (3) Context and environment of adult education and different "types" of adult educators; (4) Ownership of the adult educators' profession and professional borders: is there a professional future for adult educators?; and (5) Learning, becoming, being and growing as professional adult educator, including issues of ageing and gender. Following a preface, "Creating a Space for Learning– Reflections" (Marin Gross and Larissa Jogi), papers include: (1) Reflective Learning in Blended Process: Becoming an Adult Educator (Helena Koskinen); (2) The Status and Training Needs of Adult Educators in Hungary (Eva Farkas); (3) Adult Educator Development and Burnout: Self-Management of Generic Competences in Problem Prevention (Joanna Pitura); (4) Adult Educators–A Threatened Species in Our Education Systems (Markus Weil); (5) Changing Demands of Society and the Validity of the Training Programme for Adult Educators in Japan: Limitations on Its Present Curriculum after the 2011 Great Eastern Japan Earthquake and Future Possibilities (Naoko Suzuki); (6) The Relations of the Actors in Research, Practice and Finnish Adult Education: What Research Means for Actors of Vocational Education? (Sini Terasahde); (7) The Impact of the Validation Process on the Professional Development of Adult Educators (Simona Sava, Mariana Crasovan, and Andreea Siliman); (8) The Identity of Adult Educators in the Context of the Open University as Perceived by Themselves and Their Students: A Case Study (Maria Gravani and Georgios K. Zarifis); (9) The Relations of the Actors in Research, Practice and Policy in Norwegian Adult Education: What Research Means for Actors of Vocational Education? (Gerd Stolen); (10) Cooperation as a Central Element of Future-Oriented Adult Education (Christina Buschle, Rudolf Tippelt, and Sandra Fuchs); (11) Academic Identity of Adult Education (Anja Heikkinen); (12) The Use of Experiential Learning in the Adult Education Field (James Bradley); and (13) Interactive Professionalization in Continuing Education and Training: The Bielefeld Approach (Wolfgang Juette, Markus Walber, and Julia Behrens). An index is also included. Individual papers contain references, tables, and figures. (Contains 29 footnotes.) [Abstract modified to meet ERIC guidelines.