Southwest Quantum Information and Technology

State preparation and measurement of light with orbital angular momentum with high quality using spatial light modulators

Presenting Author: Xijie Luo, University of New Mexico
Contributing Author(s): F. E. Becerra

The Orbital Angular Momentum (OAM) degree of freedom of light provides access to a high dimensional space, which is an ideal platform for applications in communication and quantum information. However, the characterization of photons in OAM states and superpositions becomes more challenging as the dimension of the space increases. We investigate the performance of different methods used for preparation of states and projective measurements in OAM, and methods to correct for experimental imperfections. We use a spatial light modulator (SLM) to control the phase and amplitude of light for state preparation. Detection of OAM modes and superpositions is achieved by a second SLM which transforms the input state onto a Gaussian mode, and a single mode fiber works as a spatial filter. The use of SLMs to compensate for differences in efficiencies of different OAM modes allows for a good performance in state preparation and measurements. These methods are essential for our future investigations in efficient protocols for quantum state tomography of OAM states in high dimensions.

(Session 5 : Thursday from 5:00pm - 7:00 pm)