Radio Frequency Scanning Tunneling Microscopy: Instrumentation and Applications

ORAL

Abstract

A severe limitation of the scanning tunneling microscope (STM) is its low temporal resolution, originating from the diminished high-frequency response of the tunnel current readout circuitry. In order to overcome this limitation, we have built a radio-frequency STM (RF-STM). Using this instrument, we can attain electronic bandwidths as high as 10 MHz by measuring the reflection from or transmission through the tunnel junction, which is embedded in a resonant inductor-capacitor (LC) circuit. This $\sim $100-fold bandwidth improvement upon the state-of-the-art translates into fast surface topography as well as delicate measurements in mesoscopic electronics and mechanics. Broadband noise measurements across the tunnel junction using this radio-frequency-STM (RF-STM) have allowed us to perform nanoscale thermometry. Furthermore, we have detected high-frequency mechanical motion with a sensitivity approaching 15 fmHz$^{-1/2}$.

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Authors

  • Utku Kemiktarak

    Dept. of Physics, Boston University, Boston, MA 02215

  • Tchefor Ndukum

    Department of Physics, Cornell University, Dept. of Physics, Cornell University, Ithaca, NY 14853

  • Keith C. Schwab

    Department of Physics, Cornell University, Dept. of Physics, Cornell University, Ithaca, NY 14853

  • Kamil L. Ekinci

    Aerospace and Mechanical Engineering, Boston University, Boston, MA, Dept. of Aerospace and Mechanical Eng., Boston University, Boston, MA 02215