Showing 1 - 10 of 25
In quasicrystalline tilings often multifractal electronic wave functions can be found. In order to obtain a better insight into their localization properties, we study the wave functions of quasiperiodic tilings in momentum space. The models are based on one-dimensional quasiperiodic chains, in...
Persistent link: https://www.econbiz.de/10010698209
The spatial behaviour of electronic wave functions at the metal-insulator transition in disordered systems is investigated with respect to the multifractal properties. The singularity spectrum and the generalized dimensions at the critical disorder in the band centre are determined. It is shown...
Persistent link: https://www.econbiz.de/10010872843
The wave functions of the non-interacting electrons in disordered systems described by a tight-binding model with site-diagonal disorder are investigated by means of the inverse participation ratio. The wave functions are shown to be fractal objects. In three-dimensional samples, a critical...
Persistent link: https://www.econbiz.de/10010874064
The combined influence of disorder and interactions on the transport properties of electrons in one dimension is investigated. The numerical simulations are carried out by means of the Hartree–Fock-based diagonalization, a very efficient method to determine the low-energy properties of a...
Persistent link: https://www.econbiz.de/10010871691
The arbitrariness of the h-index becomes evident, when one requires q×h instead of h citations as the threshold for the definition of the index, thus changing the size of the core of the most influential publications of a dataset. I analyze the citation records of 26 physicists in order to...
Persistent link: https://www.econbiz.de/10011039449
In order to take multiple co-authorship appropriately into account, a straightforward modification of the Hirsch index was recently proposed. Fractionalised counting of the papers yields an appropriate measure which is called the hm-index. The effect of this procedure is compared in the present...
Persistent link: https://www.econbiz.de/10010795071
The citation records of 26 physicists are analyzed in order to determine the modified g index gm which takes multiple coauthorship into account by fractionalized counting of the publications. The results are compared with the original g index as well as with the h index and the respective...
Persistent link: https://www.econbiz.de/10010795125
The h-index has been shown to have predictive power. Here I report results of an empirical study showing that the increase of the h-index with time often depends for a long time on citations to rather old publications. This inert behavior of the h-index means that it is difficult to use it as a...
Persistent link: https://www.econbiz.de/10010795173
The Hirsch index h and the g index proposed by Egghe as well as the f index and the t index proposed by Tol are shown to be special cases of a family of Hirsch index variants, based on the generalized mean with exponent p. Inequalities between the different indices are derived from the...
Persistent link: https://www.econbiz.de/10010795214
A recently suggested modification of the g-index is analysed in order to take multiple coauthorship appropriately into account. By fractionalised counting of the papers one can obtain an appropriate measure which I call gm-index. Two fictitious examples for model cases and two empirical cases...
Persistent link: https://www.econbiz.de/10010795241