Harmonic Content of Strain-induced Potential Modulation in Unidirectional Lateral Superlattices

Theory of potential modulation in lateral surface superlattices.

We have calculated the piezoelectric coupling between a two-dimensional electron gas and the stress field due to a lateral surface superlattice, a periodic striped gate. The stress is assumed to arise from differential contraction between the metal gate and semiconductor. The piezoelectric potential is several times larger than the deformation potential and generally gives the dominant coupling...

Higher order terms in the geometric resonance of open orbits in unidirectional lateral superlattices

The geometric resonance of open orbits in unidirectional lateral superlattices has been examined with high magnetic-field resolution. Magnetoresistance oscillations periodic in 1/B, analogous to the well-known commensurability oscillations but orders of magnitude smaller both in magnitude and in the magnetic-field scale, have been observed superposed on the low-field positive magnetoresistance....

Anisotropic magnetization-induced second harmonic generation in FeÕAu superlattices

Dependence of Modulation Amplitude on Electron Density in Unidirectional Lateral Superlattices: The Effect of the Thickness of the Two-dimensional Electron Gas

The amplitude V0 of unidirectional periodic potential modulation introduced by a surface grating into a two-dimensional electron gas (2DEG) formed at AlGaAs/GaAs heterointerface is measured as a function of electron density ne by analyzing commensurability oscillation of the magnetoresistance. The electron density is varied either by applying a bias to a metallic back gate or by illumination. T...

the washback effect of discretepoint vs. integrative tests on the retention of content in knowledge tests

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