Real-Time Transport Properties of Multiply-Connected LaAlO$_3$/SrTiO$_3$ Nanostructures

Electronic nanostructures can be created at the LaAlO$_3$/SrTiO$_3$ interface using a conductive atomic force microscope technique\footnote{C. Cen, \textit{et al.}, Science \textbf{323}, 1026 (2009)}. These nanowires can be arranged into complex nanostructures such as photodetectors\footnote{P. Irvin, \textit{et al.}, Nature Photonics \textbf{4}, 849 (2010)} and single-electron transistors\footnote{G. Cheng, \textit{et al.}, Nature Nanotechnology \textbf{6}, 343 (2011)}. We have developed a way to characterize multi-terminal devices in real time. AC voltages at distinct frequencies are applied to every electrical contact for the device. Fourier analysis of the current response at each electrode allows the $\textit{N}$-terminal conductance matrix to be determined simultaneously.