TY - JOUR
T1 - Local imaging of high mobility two-dimensional electron systems with virtual scanning tunneling microscopy
AU - Pelliccione, M.
AU - Bartel, J.
AU - Sciambi, A.
AU - Pfeiffer, L. N.
AU - West, K. W.
AU - Goldhaber-Gordon, D.
N1 - Publisher Copyright:
© 2014 AIP Publishing LLC.
PY - 2014/11/3
Y1 - 2014/11/3
N2 - Correlated electron states in high mobility two-dimensional electron systems (2DESs), including charge density waves and microemulsion phases intermediate between a Fermi liquid and Wigner crystal, are predicted to exhibit complex local charge order. Existing experimental studies, however, have mainly probed these systems at micron to millimeter scales rather than directly mapping spatial organization. Scanning probes should be well-suited to study the spatial structure of these states, but high mobility 2DESs are found at buried semiconductor interfaces, beyond the reach of conventional scanning tunneling microscopy. Scanning techniques based on electrostatic coupling to the 2DES deliver important insights, but generally with resolution limited by the depth of the 2DES. In this letter, we present our progress in developing a technique called "virtual scanning tunneling microscopy" that allows local tunneling into a high mobility 2DES. Using a specially designed bilayer GaAs/AlGaAs heterostructure where the tunnel coupling between two separate 2DESs is tunable via electrostatic gating, combined with a scanning gate, we show that the local tunneling can be controlled with sub-250 nm resolution.
AB - Correlated electron states in high mobility two-dimensional electron systems (2DESs), including charge density waves and microemulsion phases intermediate between a Fermi liquid and Wigner crystal, are predicted to exhibit complex local charge order. Existing experimental studies, however, have mainly probed these systems at micron to millimeter scales rather than directly mapping spatial organization. Scanning probes should be well-suited to study the spatial structure of these states, but high mobility 2DESs are found at buried semiconductor interfaces, beyond the reach of conventional scanning tunneling microscopy. Scanning techniques based on electrostatic coupling to the 2DES deliver important insights, but generally with resolution limited by the depth of the 2DES. In this letter, we present our progress in developing a technique called "virtual scanning tunneling microscopy" that allows local tunneling into a high mobility 2DES. Using a specially designed bilayer GaAs/AlGaAs heterostructure where the tunnel coupling between two separate 2DESs is tunable via electrostatic gating, combined with a scanning gate, we show that the local tunneling can be controlled with sub-250 nm resolution.
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U2 - 10.1063/1.4901174
DO - 10.1063/1.4901174
M3 - Article
AN - SCOPUS:84908636865
SN - 0003-6951
VL - 105
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 18
M1 - 181603
ER -