Super sub-wavelength patterns in photon coincidence detection

TL;DR

This paper investigates super sub-wavelength interference patterns in photon coincidence detection, demonstrating how different detector scanning methods can produce patterns beyond classical resolution limits, with implications for quantum lithography.

Contribution

It provides a detailed second-order correlation analysis and experimental validation of super sub-wavelength interference patterns using pseudo-thermal and entangled light.

Findings

Super sub-wavelength interference patterns can be achieved with different detector scanning methods.

Theoretical explanation aligns with experimental results for both pseudo-thermal and entangled light.

Limitations of super sub-wavelength interference in quantum lithography are discussed.

Abstract

High-precision measurements implemented by means of light is desired in all fields of science. However, light is a wave and Rayleigh criterion gives us a diffraction limitation in classical optics which restricts to get arbitrary high resolution. Sub-wavelength interference has a potential application in lithography to beat the classical Rayleigh limit of resolution. We carefully study the second-order correlation theory to get the physics behind sub-wavelength interference in photon coincidence detection. A Young's double-slit experiment with pseudo-thermal light is carried out to test the second-order correlation pattern. The result shows that when different scanning ways of two point detectors are chosen, one can get super sub-wavelength interference patterns. We then give a theoretical explanation to this surprising result, and find this explanation is also suitable for the result by using entangled light. Furthermore, we discuss the limitation of this kind of super sub-wavelength interference patterns in quantum lithography.