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Tunneling images of a 2D electron system in a quantizing magnetic field

I. J. Maasilta·Subhasish Chakraborty·I. Kuljanishvili·S. H. Tessmer·M. R. Melloch
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Abstract

We have applied a scanning probe method, Subsurface Charge Accumulation (SCA) imaging, to resolve the local structure of the interior of a semiconductor two-dimensional electron system (2DES) in a tunneling geometry. Near magnetic fields corresponding to integer Landau level filling, submicron scale spatial structure in the out-of-phase component of the tunneling signal becomes visible. In the images presented here, the structure repeats itself when the filling factor is changed from nu=6 to nu=7. Therefore, we believe the images reflect small modulations in the 2DES density caused by the disorder in the sample.

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I. J. Maasilta, Subhasish Chakraborty, I. Kuljanishvili, S. H. Tessmer, M. R. Melloch. 2002-06-18. Tunneling images of a 2D electron system in a quantizing magnetic field. https://doi.org/10.1016/s1386-9477(02)01072-x

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