A method of exchanging quantum information between a photon and a micro/nano scale resonant structure is provided. The method comprises providing the resonant structure (15) in an optical waveguide (10). The method further comprises passing a photon (18) through the resonant structure in the optical waveguide. The method also comprises applying a driving signal (17) to the resonant structure to cause phonic oscillation of the resonant structure and to modulate a wavelength of the photon such that the passing the photon through the resonant structure results in an exchange of quantum information between the photon and a quantum state in a phonon of the resonant structure.