EXPERIMENTAL-STUDY OF REDUCED SHOT-NOISE IN A DIFFUSIVE MESOSCOPIC CONDUCTOR

We show that a diffusive narrow wire of a length much longer than the elastic scattering length and the phase-coherence length, but of the o rder of the energy relaxation length, exhibits shot noise with an inte nsity lower than the full shot-noise level. At 4.2 K, the reduction fa ctor is shown to vary between 0.2 and 0.45, depending on the width of the wire. The reduction is consistent with recent theoretical predicti ons.