Subwavelength interference with classical light

The resolution of optical interference is ultimately limited by the wavelength of light, which is known as Rayleigh criterion. Interestingly, this limitation could be surpassed by considering photonic de Broglie wave, and the resulting subwavelength interference is useful for lithography and super-resolving phase measurementsuper-resolving phase measurement. Usually, quantum entangled state is necessary to realize photonic de Broglie wave. Recent advances show that subwavelength interference could also be realized with a classical light through post-selected operation or by considering light-matter interaction. In this work, a new classical source is designed to achieve subwavelength interference without any post-selected operation in a linear scheme.