Abstract: The beam with orbital angular momentum eigenstates can be achieved transmission of high-dimensional quantum information, and this feature is used to encode information that can increase the data storage density. It presents the phase encoding method that is depending on the phase rotation angle of the incident light beam to control the phase delay, thus achieving code phase information.It also analyses the distribution of the spiral spectrum,and detects the spiral spectrum corresponding to the characteristics of the particular coding quadrant staircase structure to distinguish different data states.Each memory cell can theoretically encode 24 bits data that is three times of four quadrant staircase structure.

Key words: orbital angular momentum, quadrant staircase structure, phase encoding, spiral spectrum