info:eu-repo/semantics/article
Determination of any pure spatial qudits from a minimum number of measurements by phase-stepping interferometry
Fecha
2017-12Registro en:
Pears Stefano, Quimey Martín; Rebón, Lorena; Ledesma, Silvia Adriana; Iemmi, Claudio César; Determination of any pure spatial qudits from a minimum number of measurements by phase-stepping interferometry; American Physical Society; Physical Review A; 96; 6; 12-2017; 1-6
2469-9934
CONICET Digital
CONICET
Autor
Pears Stefano, Quimey Martín
Rebón, Lorena
Ledesma, Silvia Adriana
Iemmi, Claudio César
Resumen
We present a proof-of-principle demonstration of a method to characterize any pure spatial qudit of arbitrary dimension d, which is based on the classic phase-shift interferometry technique. In the proposed scheme a total of only 4d measurement outcomes are needed, implying a significant reduction with respect to the standard schemes for quantum-state tomography which require on the order of d^2. By using this technique, we have experimentally reconstructed a large number of states ranging from d=2 up to 14 with mean fidelity values higher than 0.97. For that purpose the qudits were codified in the discretized transverse-momentum position of single photons, once they are sent through an aperture with d slits. We provide an experimental implementation of the method based in a Mach-Zehnder interferometer, which allows one to reduce the number of measurement settings to four since the d slits can be measured simultaneously. Furthermore, it can be adapted to consider the reconstruction of the unknown state from the outcome frequencies of 4d−3 fixed projectors independently of the encoding or the nature of the quantum system, allowing one to implement the reconstruction method in a general experiment.