Microwave Diffraction

Introduction

Microwaves have wavelengths of the order of centimeters, which allows them to be used to do "macroscopic diffraction" experiments. This is instructive because one can readily see the crystal structure which is diffracting. The diffraction theory is, of course, identical to the Bragg theory which applies to electron and X-ray diffraction.

Equipment

Pasco WA-9314B Microwave Optics set, which includes:

· Transmitter

· Receiver

· Goniometer

· Reflectors, slits

· Crystal models

· Component holders

· Instruction manual

Procedure

Review the theory of microwave propagation discussed in the experiment manual and be sure that you understand it. The main purpose of this experiment is to verify that microwaves do undergo the same phenomena as waves having smaller wavelengths. Perform as many of the experiments described in the manual as you can.

References

David J. Griffiths, Introduction to Electrodynamics, Prentice Hall, Englewood Cliffs, New Jersey (1989).

D. W. Preston and E. R. Dietz, The Art of Experimental Physics, Wiley, New York (1991).

C. H. Townes and A. L. Schawlow, Microwave Spectroscopy, Dover, New York (1975).

H. C. Torrey and C. A. Whitmer, Crystal Rectifiers, MIT Radiation Lab, McGraw Hill, New York (1948).