Spin fractionalization at the edge of quantum Hall fluids induced by bulk quasiparticles

We define a measurable spin for the edge of a lowest Landau level and incompressible fractional quantum Hall state in the presence of an Abelian or non-Abelian bulk quasiparticle. We show that this quantity takes a fractional value inherited from the fractional spin of the bulk quasiparticle. We present a geometric picture that does not rely on global symmetries of the wave function, but is able to treat quasiparticles and edges with different shapes. We study finite-size many-body wave functions on the cylinder with circular quasiparticles and straight edges. Our results are supported by matrix-product-state calculations for the Laughlin and the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mi>k</a:mi><a:mo>=</a:mo><a:mn>3</a:mn></a:mrow></a:math> Read-Rezayi states.