Nonlinear Transport of 2d Electrons in Crossed Electric and Quantizing Magnetic Fields

Abstract

Nonlinear resistance of highly mobile two-dimensional electrons placed in crossed electric and strong magnetic fields attracts considerable contemporary interest. The resistance shows remarkably strong and nontrivial dependence on the electric field E in both microwave and dc responses. At small electric fields, the resistance demonstrates impressive several-fold reduction with the electric field, which is unusual for degenerate electron systems. A higher electric field induces appreciable oscillations of the resistance with both electric and magnetic fields. Zero resistance and zero differential resistance states of the 2D electrons are observed in these strongly nonlinear systems. Experiments show that the nonlinearities are related to a quantization of the electron spectrum in magnetic fields. Essential progress has been achieved in the theoretical description of dominant mechanisms responsible for the strong electron nonlinearity. The review describes recent development in this interesting area.

Nonequilibrium phenomena in high Landau levels

“…Subsequently many performed detailed analyses of such instabilities in various systems with negative differential or absolute conductivity. The corresponding literature is extensive, and we restrict ourselves to quoting several early articles (Bonch-Bruevich and Kogan, 1965;Elesin and Manykin, 1967;Ridley, 1963;Volkov and Kogan, 1967), a review by Volkov and Kogan (1969), and the books by Bonch-Bruevich et al (1975);Pozhela (1981);Schöll (2001). The interested reader can find there an overview of various mechanisms of emergence of negative conductivity (characterized by N-shape or S-shape currentvoltage-characteristics), derivation of stability conditions, and an analysis of domain formation as a result of instabilities.…”

Quantum oscillations of dissipative resistance in crossed electric and magnetic fields

“…In response to both microwave radiation and dc excitations, strongly nonlinear electron transport that gives rise to unusual electron states [38][39][40][41][42][43][44][45][46][47] has been reported and investigated. Very recent experimental studies in the low frequency domain [11,[22][23][24] reveal that the dominant mechanism of the nonlinearity is related to a peculiar quantal heating ("inelastic" mechanism [33]), which may not increase the broadening of electron distribution ("temperature") in systems with discrete spectrum [22,23]. Due to this extraordinary property, the Joule heating strongly affects the electron transport in quantum conductors.…”

Quantum lifetime of two-dimensional electrons in a magnetic field

“…In response to both microwave radiation and dc excitations, strongly nonlinear electron transport that gives rise to unusual electron states [40][41][42][43][44][45][46][47][48][49] has been reported and investigated. Very recent experimental studies of the strongly nonlinear resistance in the low frequency domain [12,[24][25][26] show that the dominant mechanism of the nonlinearity is related to a peculiar quantal heating ("inelastic" mechanism [35]), which may not increase the broadening of electron distribution ("temperature") in systems with discrete spectrum [24,25]. Microwave studies of this nonlinearity [22] indicate the relevance of another nonlinear mechanism: electric field induced variations in the kinematics of electron scattering on impurities ("displacement" mechanism [27,28,34]), which limits the lifetime of an electron in a quantum state.…”