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Уважаемые сотрудники ИТФ,<br>
<br>
В пятницу 22 февраля состоится коллоквиум с докладом:<br>
<br>
Ferdinand Evers (Regensburg University)<b><br>
</b><b>Recent theoretical developments in the integer quantum Hall
effects</b><br>
<br>
The quantum Hall effects belong to the most striking phenomena in
condensed matter physics. Despite of intensive theoretical efforts
over the last three decades, important aspects of the quantum Hall
transitions are still not fully understood. In particular, there is
still no consensus concerning the critical field theory and the
corresponding scaling properties of the observables near and at the
plateau transition.<br>
Notwithstanding this status, the last ten years have seen
considerable progress in understanding basic properties of scaling
near localization-delocalization transitions that have implications
also for the quantum Hall transition. These concern, e.g., the
important topic of corrections to scaling, the wavefunction
statistics and higher-order multifractality. A brief review of these
developments will be offered in the first part of the talk.<br>
The second part of the talk will be devoted to the spin quantum Hall
effect, which is a variant of the integer quantum Hall effect (class
A) taking place in the Altland-Zirnbauer class C. For this
transition several critical exponents are known analytically and can
serve as reference points. Therefore, this transition provides an
ideal testbed for the qualitative predictions made by analytical
theories. Analytical predictions will be confronted with most recent
numerical results. <br>
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