EFFICIENT GENERATION OF HIGH DIMENSION PHOTONIC STATES

J. J. M. VARGA; L REBÓN; M. A. SOLÍS-PROSSER; L. NEVES; S. LEDESMA; C. IEMMI

Mar del Plata

Conferencia; Quantum Optics VII; 2014

We present a method for preparing arbitrary pure states of spatial qudits, namely, D-dimensional (D > 2) quantum systems carrying information in the transverse momentum and position of single photons. For this purpose, a set of D slits with complex transmission are displayed on a spatial light modulator (SLM). This method requires a single phase-only SLM to control independently the complex coefficients which define the quantum state of dimension D. The amplitude information is codified by introducing phase gratings inside eachslit and the phase value of the complex transmission is added to the phase gratings. After a spatial filtering process we obtain in the image plane the desired qudit state. This method is a good alternative to compact the previously reported architectures, being much simpler, less costly, and more efficient. Furthermore, we present an alternative scheme to codify the required phase values that minimizes the effects of temporal phase fluctuations associated to the SLM where the codification is carried on. In this scheme the amplitudes are set by appropriate phase gratings addressed at the SLM while the relative phases are obtained by a lateral displacement of these phase gratings. We show that this method improves the quality of the prepared state and provides very high fidelities of preparation for any state.