Beyond the Rayleigh limit in optical lithography

Suhail Zubairy (Texas A&M University)

In optical lithography, the feature size in which scientists can write the circuits is limited to half 
the wavelength of the light by something called the diffraction limit. Many attempts have been
 made to advance this field beyond the current limit set by the wavelength of the laser used. 
These methods are usually based on multi-photon processes, multiple beams and/or quantum 
entanglement making the implementation of these schemes extremely difficult. In this talk, I shall 
discuss these methods and then present a method for optical sub-wavelength lithography that is
 only a single preparation step away from the currently implemented lithographic process. 
During this crucial step, the electrons in the energy levels undergo oscillations called Rabi 
oscillations between the ground and auxiliary levels. Nonlinear nature of Rabi oscillations allows 
for sub-wavelength control of atomic excitation. This method can allow, in principle, to write a 
pattern with an accuracy better than a millionth of the wavelebngth of the light used.