Affiliation
Novosibirsk State University
Title
Unusual mesoscopic conductance fluctuations in 2D HgTe semimetal
Abstract
Mesoscopic conductance fluctuations were discovered in a weak localization regime of strongly disordered two-dimensional HgTe based semimetal. Those fluctuations exist in macroscopic samples with characteristic sizes about 100 mkm and have anomalous dependences on the gate voltage, magnetic field and temperature. They are absent in the regime of electron metal and they strongly depend on the level of disorder in the system. All the experimental facts let us to a conclusion that the origin of the fluctuations is a special collective state in which the current is conducted through the percolation network of electron resistances. The network is formed by fluctuation potential whose amplitude is higher than Fermi level of electrons due to their very low density.