We present a microscopic theory of the collective modes of a ‘‘smooth’’ edge of a quantum Hall system, showing under what conditions these modes can be described as a set of independent bosons. We then calculate the electronic spectral function in an independent-boson model—a procedure that reduces to standard bosonization in the limit of ‘‘sharp’’ edge. The I-V tunneling characteristics deduced from this model exhibit, for low voltage, a power-law behavior, with exponents that differ significantly from those of the sharp edge model. © 1996 The American Physical Society.

• Received 28 August 1996

DOI:https://doi.org/10.1103/PhysRevB.54.R14309