Determination of density of states of thin high-TcT_c films by FET type microstructures

A simple electronic experiment with a field effect transistor type microstructure is suggested. The thin superconductor layer is the source-drain channel of the layered structure where an AC current is applied. It is necessary to measure the second harmonic of the source-gate voltage and third harmonic of the source-drain voltage. The electronic measurement can give the logarithmic derivative of the density of states which is an important parameter for fitting of parameters of the band structures.Comment: 3 pages, 1 figur

Limit theorems for maxima of heavy-tailed terms with random dependent weights

We study the general case when the weights Wj , j N can be dependent and in particular long-range dependent. Under mild tail and convergence conditions on the weights Wjs, we establish limit theorems for scaled versions of the process fMn(t)gt_0, as n ! 1. The limit processes are mixtures of extremal Frechet processes. The results are valid when the laws of the Uj’s belong to the normal domain of attraction of a Frechet distribution or to a sub-class of the general domain of attraction of a Frechet law

Weak convergence to the tangent process of the linear multifractional stable motion

We also show that one can have degenerate tangent processes Z(t), when the function H(t) is not sufficiently regular. The LMSM process is closely related to the Gaussian multifractional Brownian motion (MBM) process. We establish similar weak convergence results for the MBM