# Is it necessary to achieve sub-wavelength interference with correlation?

## TL;DR

This paper demonstrates that sub-wavelength interference effects can be achieved without correlation measurements by using a thermal light source and intensity thresholding, challenging the conventional reliance on correlation.

## Contribution

It introduces a novel method to observe sub-wavelength interference without correlation, using intensity restrictions on thermal light sources.

## Key findings

- Sub-wavelength interference observed without correlation measurement.
- Positive and negative interference patterns demonstrated.
- Thermal light source can produce sub-wavelength effects independently.

## Abstract

We report an experimental demonstration of sub-wavelength interference without correlation. Typically, people can achieve sub-wavelength effect with correlation measurement no matter by using bi-photon or thermal light sources. Here we adopt a thermal light source. And we count the realizations in which the intensities of the definite symmetric points are above or below a certain threshold. The distribution of numbers of these realizations who satisfy the restriction will show a sub-wavelength effect. With proper constrictions, positive and negative interference patterns are demonstrated.