1. 35 th International Physics Olympiad Pohang, Korea 15 ~ 23 July 2004 Theoretical Competition Saturday, 17 July 2004 Theoretical Question 3

2. 35th International Physics Olympiad Theoretical Competition, Saturday, 17 July 2004 “Scanning Probe Microscope” Theoretical Question 3: “Scanning Probe Microscope” Objective: To locate a single electron under the surface

3. 35th International Physics Olympiad Theoretical Competition, Saturday, 17 July 2004 lock-in amplifier piezotube F VRVR ViVi input ref. m phase shifter sample k m piezotub e F k laser z=0 output signal V i =c 2 z photo-detector Cantilever “Scanning Probe Microscope” Theoretical Question 3: “Scanning Probe Microscope” Problem design: Harmonic Oscillator Harmonic Waves Hooke’s Law Coulomb’s Law

4. 35th International Physics Olympiad Theoretical Competition, Saturday, 17 July 2004 “Scanning Probe Microscope” Theoretical Question 3: “Scanning Probe Microscope” Physical concepts required: Oscillations  Harmonic Oscillations  Harmonic Waves  Resonance Electricity  Coulomb’s Law Mechanics  Hooke’s Law  Force Equilibrium