The assignment of nano technology.

1. You are in the business of designing nanoparticle sensors. A typical metallic nanopaticle has a mass of 1x10^-15 Kg and an energy of 1 eV (Electron Volt). These nanoparticles are detected when they impinge on the surface of the detector. The surface of the detector is fabricated with a thin film of Gold. The typical surface binding energy of such a gold film is 3 eV.

(i) What would be the wavelength of a typical nanoparticle?

(ii) What should be the thickness of the Gold film so that 20% of the nanoparticles can tunnel through it (and be detected) , while 80% is reflected back. Explain the assumptions made in the calculation?

2. The bound state wave function for a nanoparticle inside a quantum well (width = W and height P_o) is

Ψ(x) = B cos(4Πx / 5W) for W/2<= x<=W/2

Ψ(x) = A exp(-|αx|) for everywhere else

(i) Find the (first energy level ground State energy) of the nanoparticle in terms of its mass (m) and the width of the well (W).

(ii) What will this energy be if the depth of the quantum well is significantly (factor of 1000) larger that its width

3. What are the instruments of nanoscience? Name at least 3 different classes of instruments that are used in characterization of nanomaterials. Explain principle of operation of each. Give examples of scientific problems that are investigated with these instruments.

Qualify the analytical capabilities of these instruments.

(b) You have obtained some ZnO₂ nanoparticles from an unknown source. Using what measurements and with what instruments would you find the following -- explain

a. The average length and diameter of the nanoparticles

b. The lattice structure of the nanoparticle surface

c. The work-function of the material

d. The elasticity of the nanoparticles

e. The stoichiometry of the material

(c) What is a Scanning Probe Microscope? How is a Scanning Probe Microscope different from an Electron Microscope? A new nano-protein structure has been predicted that can bind with the HIV virus and prevent it from spreading. You have been given the charge to observe and verify this hypothesis.

What characterizing instruments you will be using and how will you be doing it?

4. (a) What is MEMS? What is NEMS? What are their differences? How can Nanotechnology improve in the manufacture and performance of them?

(b) What are different fabrication techniques for MEM devices? What are their problems? How can they be rectified?

(c ) Give an example of a NEMS device in the process of being commercialized? Show how it works and its advantages.

5. Answer any 5parts out of the 8 asked in this question.

(a) What is a nanogenerator? How is it different from a rechargeable battery? What are its advantages and drawbacks? Explain how a the following Nanogenerators function

(i) Triboelectric Nanogenerator?

(ii) PCB based Nanogenerator?

(b) What are the assumptions that need to be satisfied to use CNT as a transmission line? Where can this be used practically?.

(c) What is quantum Computing? How can Nanotechnology help us in achieving this? What are reversible computers ? What is quantum cost? Explain how reversible computers can improve computing efficiency with respect to time and energy used

(d) What are the advantages of CNT based TUBEFETs? What is the problem if the CNT has metallic impurities/defects. Explain how these metallic defects in CNT can be detected.

(e) Why do we need to efficiently manage the thermal energy for power electronic applications? Briefly describe how is this thermal management is performed. How nanotechnology help us in doing a better and more efficient thermal management

(f) Why is it necessary to sort CNT based on its diameter? Which property of the CNT changes with diameter? Explain some techniques of sorting the CNT according to its diameter.

(g) Compare and contrast the nanotechnology based electrochemical and optical sensing techniques for detection of glucose levels in blood. Which technique do you think is better and why?

(h) What are cancer biomarkers? How nanotechnology can improve the performance of biomarkers? How nanotechnology can help in the cure of skin cancer.