Answer Happy

The next two questions pertain to the situation described below. A scanning tunneling microscope (STM) uses electrons that tunnel from the (metal) surface of the object-to-be- measured into the sharp STM tip to map out the surface profile as the tip is scanned across the surface. The energy of the electrons is 2 eV and the height of the barrier is 2.5 eV when the gap between the tip of STM and the metal surface is 0.5 nm. Recall that the transmission coefficient is given by T = Ge-2x1, where G = 16(1-5). Vietal tip material STM tip АЛ, Nm N M M Mal M Z 16) What is the tunneling probability of the electrons? a. 0.071 b. 0.027 c. 7.5 x 10-4 d. 0.14 e. 0.055 17) If the gap between the tip and the surface of the sample is decreased by a factor of two, what happens to the transmission probability? a. It increases by a factor of 6. b. It increases by a factor of 3. c. It decreases by a factor of 2. d. It decreases by a factor of 4. e. It does not change.