Series of magnetoresistance oscillations of a two-dimensional electron gas in a strong periodic magnetic modulation
نویسندگان
چکیده
A nonperturbative technique is used to calculate the magnetoresistance of two-dimensional electron gases ~2DEG! subjected to a spatially periodic magnetic field B1 with period a in addition to a uniform magnetic field B0 in the same direction. For small amplitude modulation, magnetoresistance exhibits oscillations similar to the Weiss oscillations observed in 2DEG under spatially periodic electric field and uniform magnetic field. In general, the oscillation is characterized by two ratios: b52pl/a and g5B1 /B0, at low magnetic modulations, with l being the magnetic length corresponding to B0. Quenching of Weiss oscillations first appears as g increases for fixed B0, and a series of oscillations then appears in our nonperturbative calculation for larger g . The temperature dependence of these oscillations shows that the basic mechanism of the production of these oscillations is similar to the Weiss oscillations. @S0163-1829~97!06307-8#
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