Single-electron charging
using atomic force microscopy

Antoine Roy-Gobeil

Department of Physics
McGill University
Montreal, Canada
November 1st 2016


Measure the electronic structure of nanostructures such as self-assembled quantum dots and molecules.

Hanadi Sleiman's group at McGill University,

Challenge and why AFM is useful

By using the AFM tip as a movable electrode, transport experiment can be performed at the nanoscale

Single-electron charging with AFM


Bennett et al., Phys. Rev. Lett. 104, 017203 (2010)

Linear response

Key result from quantum linear response theory* is that the total tunneling rate determines the ratio of the change in frequency shift and dissipation:

Not found

Tunneling rate contains information about the density of state/electronic structure

*In the regime of weak coupling
Clerk et al., New J. Phys., 7 238 (2005)

Tunneling rates

Tunneling rate - Single non-degenerate level

Beenhaker et al., Physical Review B 44, 1646–1656 (1991)

Metallic grains

Au nanoparticles @ 77K

Not found

Au nanoparticles @ 77K

Tunneling rate - Continuous Density of States

Quantum dots

InAS QD @ 4K

Cockins et al., Proc. Natl. Acad. Sci. USA 107, 9496 (2010)

InAs QD @ 4K - Degenerate levels (s-shell)

Tunneling rate - Degenerate level (v=2,n_shell=0)

Tunneling rate - Degenerate level (v=2,n_shell=1)

InAs QD @ 4K - Degenerate levels (s-shell)


Effect of the reorganization energy

Not found

Amplitude-dependent response

Preliminary observations on ferrocene molecule

Experimental challenges

Sample preparation

InAs QD / InP

Cockins et al., PNAS (2010)

Au cluster / NaCl / Fe

Tekiel et al., ACSNano (2013)

Au NP / C16S2 / Au

Roy-Gobeil et al., NanoLetters (2015)

Accurate dissipation measurement

Labuda et al., Physical Review B 84, 125433 (2011)

Sensitive low-temperature atomic force microscopy



Using AFM to probe coherent inter quantum dot tunneling and possibly measure the value of the double-dot relaxation time.

J. Gardner et al., Physical Review B 84, 205316 (2011)




  • Hanadi Sleimann
  • Kai Lin Lau


  • Aashish Clerk
  • Steve Bennett
  • Jamie Gardner


  • Peter Grutter
  • Yoichi Miyahara
  • Lynda Cockins