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تسجيل مستخدم جديدFractional statistics in anyon collisions
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Two-dimensional systems can host exotic particles called anyons whose quantum statistics are neither bosonic nor fermionic. For example, the elementary excitations of the fractional quantum Hall effect at filling factor $ u=1/m$ (where m is an odd integer) have been predicted to obey abelian fractional statistics, with a phase $varphi$ associated with the exchange of two particles equal to $pi/m$. However, despite numerous experimental attempts, clear signatures of fractional statistics remain elusive. Here we experimentally demonstrate abelian fractional statistics at filling factor $ u=1/3$ by measuring the current correlations resulting from the collision between anyons at a beam-splitter. By analyzing their dependence on the anyon current impinging on the splitter and comparing with recent theoretical models, we extract $varphi=pi/3$, in agreement with predictions.
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