2016/01/21 by James M. Ashby, Peter D. Schwarz, Maximilian Schlosshauer
Computer Science · Physics and Astronomy · #Computer science #Detector #Erasure #Mechanical and Optical Resonators #Optics #Photon #Physics #Polarization (electrochemistry) #Quantum #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum imaging #Quantum information #Quantum mechanics #Quantum network #Quantum optics #quant-ph
paper · pdf · doi:10.1119/1.4938151
published as Am. J. Phys. 84, 95-105 (2016) · 13 pages, 5 figures, identical to published version
openalex publication_date 2016/01/21 · arxiv created 2016/01/22 · arxiv updated 2016/01/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In a delayed-choice quantum eraser, interference fringes are obtained by erasing which-way information after the interfering particle has already been irreversibly detected. Following an introductory review of delayed-choice experiments and quantum erasure, we describe the experimental realization of an optical delayed-choice quantum eraser, suitable for advanced undergraduates, based on polarization-entangled pairs of single photons. In our experiment, the delay of the erasure is implemented using two different setups. The first setup employs an arrangement of mirrors to increase the optical path length of the photons carrying which-way information. In the second setup, we use fiber-optic cables to elongate the path of these photons after their passage through the polarization analyzer but prior to their arrival at the detector. We compare our results to data obtained in the absence of a delay and find excellent agreement. This shows that the timing of the erasure is irrelevant, as also predicted by quantum mechanics. The experiment can serve as a valuable pedagogical tool for conveying the fundamentals of quantum mechanics.