Which tunnel faster across a quantum Hall strip: fractional charges or electrons?

Abstract

The tunneling rate of fractional charge across a Laughlin state on the cylinder is computed numerically. The decay with strip width Y is fitted to exp[- a (Y/ l)**2/12] where l is the Landau length, and a is approximately 1.0. This rate is exponentially LARGER than the electron tunneling rate and can be interpreted by analogy to a superfluid vortex tunneling problem. Experimental implications include the ``law of corresponding states'', periodicity of Aharonov-Bohm resistance oscillations and charge measurements by quantum shot noise.