Resonance oscillations of magnetoresistance in double quantum wells

Abstract

We present experimental and theoretical studies of the magnetoresistance oscillations induced by resonance transitions of electrons between tunnel-coupled states in double quantum wells. The suppression of these oscillations with increasing temperature is irrelevant to the thermal broadening of the Fermi distribution and reflects the temperature dependence of the quantum lifetime of electrons. The gate control of the period and amplitude of the oscillations is demonstrated.Comment: 5 pages 4 figures, to be published in the Physical Review

Microwave-induced Hall resistance in bilayer electron systems

“…This statement is well justified from the point of view of bulk transport theory and is confirmed in numerous experiments. [8][9][10][11]18,[23][24][25] In addition, the theoretical model of dissipative MW photoresistance based on a consideration of the inelastic mechanism 6 explains satisfactorily all features of MIRO's (including frequency, power, and temperature dependence) for different two-subband systems studied in our experiments (see, e.g., Refs. 8 and 10).…”

Quantum electron transport in magnetically entangled subbands

“…To analyze the spectrum the obtained eigenvalues of the Hamiltonian are numerated in ascending order using positive integer index l=1,2.... Eqs. (8,9,10) yield the electron spectrum obtained in a rigid electrostatic potential V (z) that provides a good agreement with experimental data. We relate this agreement with a large gap ∆ 12 between subbands indicating strong electrostatic potential V (z) in the system.…”

“…An in-plane magnetic field, B , provides an additional coupling via Lorentz force coming from the last term in Eq. (8). This additional B -coupling preserves the degeneracy of the quantum levels but induces variations of the electron spectrum, which, due to a relativistic origin of Lorentz force, are dependent on the energy (velocity).…”

“…(9) describes diamagnetic shift of the quantum levels and is related to the fifth term in Eq. (8). In the basis set |N, ξ the diamagnetic term is proportional to ξ|z 2 |ξ .…”

“…[5][6][7][8][9][10] These magneto-inter-subband oscillations (MISO) of the resistance are due to an alignment between Landau levels from different subbands i and j with corresponding energies E i and E j . Resistance maxima occur at magnetic fields at which the gap between the bottoms of subbands, ∆ ij = E i − E j , equals a multiple of the Landau level spacing,hω c : ∆ ij = k ·hω c , where k is an integer [11][12][13][14] .…”