Measurements of quasi-particle tunneling in the nu = 5/2 fractional quantum Hall state

摘要

Some models of the 5/2 fractional quantum Hall state predict that thequasi-particles, which carry the charge, have non-Abelian statistics: exchangeof two quasi-particles changes the wave function more dramatically than justthe usual change of phase factor. Such non-Abelian statistics would make thesystem less sensitive to decoherence, making it a candidate for implementationof topological quantum computation. We measure quasi-particle tunneling as afunction of temperature and DC bias between counter-propagating edge states.Fits to theory give e*, the quasi-particle effective charge, close to theexpected value of e/4 and g, the strength of the interaction betweenquasi-particles, close to 3/8. Fits corresponding to the various proposed wavefunctions, along with qualitative features of the data, strongly favor theAbelian 331 state.