Searcharxiv⌕ Search

arXiv subjects

V. Freilikher

Publications and source records attributed to V. Freilikher.

20 records · Page 2Linked to original sources

Unitary Random-Matrix Ensemble with Governable Level Confinement

A family of unitary $α$-Ensembles of random matrices with governable confinement potential $V(x) ~ |x|^α$ is studied employing exact results of the theory of non-classical orthogonal polynomials. The density of levels, two-point kernel, locally rescaled two-level cluster function and smoothed connected correlations between the density of eigenvalues are calculated for strong ($α> 1$) and border ($α= 1$) level confinement. It is shown that the density of states is a smooth function for $α> 1$, and has a well-pronounced peak at the band center for $α<= 1$. The case of border level confinement associated with transition point $α= 1$ is reduced to the exactly solvable Pollaczek random-matrix ensemble. Unlike the density of states, all the two-point correlators remain (after proper rescaling) to be universal down to and including $α= 1$.

cond-mat↗

Enhanced Transmission Through Disordered Potential Barrier

Effect of weak disorder on tunneling through a potential barrier is studied analytically. A diagrammatic approach based on the specific behavior of subbarrier wave functions is developed. The problem is shown to be equivalent to that of tunneling through rectangular barriers with Gaussian distributed heights. The distribution function for the transmission coefficient $T$ is derived, and statistical moments $\left< T^n\right>$ are calculated. The surprising result is that in average disorder increases both tunneling conductance and resistance.

cond-mat↗