1. Questions How does a scanning tunneling microscope measure the thermal expansion of gold? How does a scanning tunneling microscope measure the thermal expansion of gold? How much does the gold sample expand when it is shot with the <80mW laser? How much does the gold sample expand when it is shot with the <80mW laser? How much of the expansion is due to the mica that the gold sample is evaporated on? How much of the expansion is due to the mica that the gold sample is evaporated on? Is the platinum-iridium tip expanding when the laser is shot? Is the platinum-iridium tip expanding when the laser is shot?

3. Single Line Scanning We use single line scans in order to measure the amount that a sample expands when it is shot by the laser. We use single line scans in order to measure the amount that a sample expands when it is shot by the laser. By using data analysis software we are able to create a graph of the thermal expansion by dividing the image into sections. By using data analysis software we are able to create a graph of the thermal expansion by dividing the image into sections.

5. Effect of Rapid Laser Heating on the Au(111) sample Attempting to prove calculated data with experimental data: Attempting to prove calculated data with experimental data: Using a COMSOL a thermodynamics software I have calculated a 10.712 K temperature increase of the Au(111) sample when it is shot with the laser. Using a COMSOL a thermodynamics software I have calculated a 10.712 K temperature increase of the Au(111) sample when it is shot with the laser. In COMSOL I created models with the exact dimensions of the sample and sample holder then applied a heat flux to the gold surface. In COMSOL I created models with the exact dimensions of the sample and sample holder then applied a heat flux to the gold surface. I have been attempting to confirm these calculated results with experimental data. I have been attempting to confirm these calculated results with experimental data.

6. COMSOL model

8. Setup for Experiment Wooden box constructed with insulating acoustic foam and cork board. Wooden box constructed with insulating acoustic foam and cork board. BNC connector BNC connector Stabilizing Base Magnets Stabilizing Base Magnets Vice Grip mount with <80mW 532nm laser Vice Grip mount with <80mW 532nm laser Isolating hanging springs Isolating hanging springs Air table Base Air table Base Piezoelectric Tube Piezoelectric Tube Sample holder with conical hole for shooting the laser through. Sample holder with conical hole for shooting the laser through. Microtherm thin-sheet insulator between the sample holder and sample to reduce the amount of heat being conducted away from the Au(111) sample when it is shot with the laser. Microtherm thin-sheet insulator between the sample holder and sample to reduce the amount of heat being conducted away from the Au(111) sample when it is shot with the laser. Electronics for the STM Electronics for the STM

9. Conclusions from experimental data When shot with the 6000 angstroms. When shot with the 6000 angstroms. There is no observed change and/or rearranging of the gold surface molecules when shot with the laser. There is no observed change and/or rearranging of the gold surface molecules when shot with the laser. From the before and after images were acquired from scanning there appeared to be no change. From the before and after images were acquired from scanning there appeared to be no change. The taking of before and after images was difficult because of thermal drift. The area scanned before the laser was shot and after most often were not the same location. The shooting of the laser itself creates a large amount of thermal drift. The taking of before and after images was difficult because of thermal drift. The area scanned before the laser was shot and after most often were not the same location. The shooting of the laser itself creates a large amount of thermal drift.

10. Further Research Set up the laser so that the laser is not run on batteries. Set up the laser so that it can be plugged into the wall thus ensuring that the laser is always receiving the same amount of power (batteries lose power over time). Set up the laser so that the laser is not run on batteries. Set up the laser so that it can be plugged into the wall thus ensuring that the laser is always receiving the same amount of power (batteries lose power over time). Install some device that allows you to detect or observe if the laser has moved when the box in which the STM is located in closed. Install some device that allows you to detect or observe if the laser has moved when the box in which the STM is located in closed. Scan other samples (C60 and C70 buckey balls on gold and octanethiols on gold) and rapidly heat them with a laser. Scan other samples (C60 and C70 buckey balls on gold and octanethiols on gold) and rapidly heat them with a laser.