Publication Type
Journal
Journal Name
Physical Review Letters
Publication Date
Page Number
226804
Volume
99
Issue
22
Abstract
We report a study of the dynamic response of electrons in a nanowire or a two-dimensional electron gas under a capacitively coupled ''spot gate'' driven by an AC voltage. A standing wave with wavevector equal to twice the Fermi wavevector is formed near the spot gate and near edges and boundaries, analogous to the static Friedel oscillations near defects at equilibrium. From the spatial modulation and resonance frequencies of the standing Friedel wave (SFW), electronic properties of nanoscale devices, including the Fermi velocity and eigenenergy spacings, can be measured directly.