Reflectance fluctuations in an absorbing random waveguide
We study the statistics of the reflectance (the ratio of reflected and incident intensities) of an N-mode disordered waveguide with weak absorption g per mean free path. Two distinct regimes are identified. The regime γ N2≫1 shows universal fluctuations. With increasing length L of the waveguide, the variance of the reflectance changes from the value 2/15N2, characteristic for universal conductance fluctuations in disordered wires, to another value 1/8N2, characteristic for chaotic cavities. The weak-localization correction to the average reflectance performs a similar crossover from the value 1/3N to 1/4N. In the regime γ N2≫1, the large-L distribution of the reflectance R becomes very wide and asymmetric, P(R)∝(1−R)−2 for R≪1−γN.
PACS numbers05.40.+j 42.25.Bs 78.20.Ci
Unable to display preview. Download preview PDF.
- 1.A. D. Stone, P. A. Mello, K. A. Muttalib, and J.-L. Pichard, in Mesoscopic Phenomena in Solids, Eds. B. L. Al’tshuler, P. A. Lee, and R. A. Webb, North Holland, Amsterdam, 1991; C. W. J. Beenakker, Rev. Mod. Phys., to appear.Google Scholar
- 8.O. N. Dorokhov, Zh. Éksp. Teor. Fiz. 85, 1040 (1983) [Sov. Phys. JETP 58, 606 (1983)].Google Scholar
- 9.T. Sh. Misirpashaev, J. C. J. Paasschens, and C. W. J. Beenakker, unpublished.Google Scholar
- 11.C. W. J. Beenakker, Phys. Rev. B 47, 15763 (1993).Google Scholar