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Probability Distribution of Conductance and Transmission Eigenvalues. Zhou Shi and Azriel Z. Genack Queens College of CUNY. Measurement of transmission matrix t. Frequency range: 10-10.24 GHz: Wave localized 14.7-14.94 GHz: Diffusive wave. b. a. t ba.
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Probability Distribution of Conductance and Transmission Eigenvalues Zhou Shi and Azriel Z. Genack Queens College of CUNY
Measurement of transmission matrix t Frequency range: 10-10.24 GHz: Wave localized 14.7-14.94 GHz: Diffusive wave b a tba
Measurement of transmission matrix t Number of waveguide modes : N~ 30 localized frequency range N~ 66 diffusive frequency range N/2 points from each polarization t : N×N L = 23, 40, 61 and 102 cm
Transmission eigenvalues tn τn: eigenvalue of the matrix product tt† Landauer, Fisher-Lee relation R. Landauer, Philos. Mag. 21, 863 (1970).
Transmission eigenvalues tn Most of channels are “closed” with τn 1/e. Neff ~ g channels are “open” with τn ≥ 1/e. O. N. Dorokhov, Solid State Commun. 51, 381 (1984). Y. Imry, Euro. Phys. Lett. 1, 249 (1986).
Spectrum of transmittance T and tn Z. Shi and A. Z. Genack, Phys. Rev. Lett. 108, 043901 (2012)
Scaling and fluctuation of conductance P(g) is a Gaussian distribution P(lng) is predicted to be highly asymmetric P(lng) is Gaussian with variance of lng, σ2 = -<lng> K. A. Muttalib and P. Wölfle, Phys. Rev. Lett. 83, 3013 (1999).
Probability distribution of the spacing of lnτn, s t is a complex matrix Wigner-Surmise for GUE
Probability distribution of optical transmittance T V. Gopar, K. A. Muttalib, and P. Wölfle, Phys. Rev. B 66, 174204 (2002).
Single parameter scaling Leff = L+2zb, zb: extrapolation length P. W. Anderson et al. Phys. Rev. B 22, 3519 (1980).
Universal conductance fluctuation R. A. Webb et. al., Phys. Rev. Lett. 54, 2696 (1985). P. A. Lee and A. D. Stone, Phys. Rev. Lett. 55, 1622 (1985). B. L. Altshuler, JETP Lett. 41, 648 (1985).
Level repulsion Neff ~ g with τn ≥ 1/e. Poisson process: var(Neff)~ <Neff> var(g)~ <g> Observation: var(g) independent of <g> Y. Imry, Euro. Phys. Lett. 1, 249 (1986).
Level repulsion and Wigner distribution Y. Imry, Euro. Phys. Lett. 1, 249 (1986). K. A. Muttalib, J. L. Pichard and A. D. Stone, Phys. Rev. Lett. 59, 2475 (1987).
Level rigidity Random ensemble Single configuration F. J. Dyson and M. L. Mehta, J. Math. Phys. 4, 701 (1963).
Level rigidity N(L) L In an interval of length L, it is defined as the least-squares deviation of the stair case function N(L) from the best fit to a straight line Wigner for GUE Poisson Distribution Δ(L)=L/15 F. J. Dyson and M. L. Mehta, J. Math. Phys. 4, 701 (1963).
Conclusions: 1. Relate the distribution of conductance to underlying transmission eigenvalues
Conclusions: 1. Relate the distribution of conductance to underlying transmission eigenvalues 2. Observe universal conductance fluctuation for classical waves
Conclusions: 1. Relate the distribution of conductance to underlying transmission eigenvalues 2. Observe universal conductance fluctuation for classical waves 3. Observe weakening of level rigidity when approaching Anderson Localization