Quantum lithography with classical light
Wenchao Ge, P. R. Hemmer, and M. Suhail Zubairy
Accepted
The concept of performing quantum lithography with classical, instead of entangled, light is of great interest for practical implementation. One recent proposal [Hemmer, Muthukrishnan, Scully, and Zubairy, Phys. Rev. Lett. 96, 163603 (2006)] to accomplish this was based on the use of frequency selective multi-photon transitions in a two-level atom. To analyze this possibility we investigate a four-level system theoretically and show that a high-resolution lithography is possible. We quantitatively identify conditions under which high-contrast lithography can be performed without sacrificing high-resolution. The approach is perturbative density matrix method. This model identifies the resolution/contrast tradeoff as being due to higher-order terms from intermediate-level Rabi oscillations. We propose using positive and negative one-photon detunings to suppress this effect. Allowing higher Rabi frequencies means that shorter interaction time can be used and this overcomes the degradation in contrast due to population decay. Finally, we generalize our scheme to N-photon lithography.