Collective response in the microwave photoconductivity of Hall bar structures

Terahertz photovoltaic detection of cyclotron resonance in the regime of radiation-induced magnetoresistance oscillations

“…69 In a finite size specimen, the length scale set by the sample boundary can determine the plasmon (ω p ) response with k = π/W , where W is the Hall bar width. 70 As mentioned, although the contacts utilized in the P V measurement are nominally ohmic, there is non-linearity in the I − V characteristics of the contacts. Photo-excitation of a 2DES with terahertz radiation can produce inter-Landau level transitions when the radiation energy equals the Landau level spacing in the presence of a perpendicular magnetic field, i.e., hf =hω c , see Fig.…”

Theory of microwave-induced zero-resistance states in two-dimensional electron systems

“…1 a very similar microwave photoresistance experiment was performed in the same experimental group by Vasiliadou et al 5 . The only difference between the old (1993) and new (2002) experiments was the mobility of the samples (µ 10 6 cm 2 /Vs in 1993 and µ ≃ 2 × 10 7 cm 2 /Vs in 2002); all other parameters, such as the electron density, the sample dimensions, the microwave frequency, the temperature, were the same.…”

“…In the absorption experiments the main contribution to the measured signal is given by the bulk electrons 'b'. They move in the screened electric field (3) and absorb the microwave energy at the magnetoplasmon frequency (5). Since the field in the bulk is weakly inhomogeneous on the cyclotron radius scale, the absorption spectra do not demonstrate any nonlocal resonances (Bernstein modes).…”

Circular-Polarization-Dependent Study of the Microwave Photoconductivity in a Two-Dimensional Electron System

“…Original photoconductivity experiments on lower quality samples only revealed the intuitively expected feature due to resonant heating at the cyclotron resonance or more accurately -due to the finite size of the sample -at the combined dimensional plasmon cyclotron resonance frequency [8]. Unanticipated 1/B-periodic oscillations with minima close to the harmonics of the cyclotron resonance first entered the scene [9,10].…”

“…The recent discovery of zero resistance induced by microwaves [1,2,3,4,5,6,7] in ultra-clean twodimensional electron systems (2DES) over extended regions of an applied perpendicular magnetic field B has revived the general interest in microwave photoconductivity and has triggered a remarkably large and diverse body of theoretical works. Original photoconductivity experiments on lower quality samples only revealed the intuitively expected feature due to resonant heating at the cyclotron resonance or more accurately -due to the finite size of the sample -at the combined dimensional plasmon cyclotron resonance frequency [8]. Unanticipated 1/B-periodic oscillations with minima close to the harmonics of the cyclotron resonance first entered the scene [9,10].…”