Quantum information processing by weaving quantum Talbot carpets

Osvaldo Jiménez Farías, Fernando De Melo, Pérola Milman, Stephen P. Walborn

Research output: Indexed journal article Articlepeer-review

19 Citations (Scopus)


Single-photon interference due to passage through a periodic grating is considered in a novel proposal for processing D-dimensional quantum systems (quDits) encoded in the spatial degrees of freedom of light. We show that free-space propagation naturally implements basic single-quDit gates by means of the Talbot effect: an intricate time-space carpet of light in the near-field diffraction regime. By adding a diagonal phase gate, we show that a complete set of single-quDit gates can be implemented. We then introduce a spatially dependent beam splitter that allows for projective measurements in the computational basis and can be used for the implementation of controlled operations between two quDits. Universal quantum information processing can then be implemented with linear optics and ancilla photons via postselection and feed-forward following the original proposal of Knill-Laflamme and Milburn. Although we consider photons, our scheme should be directly applicable to a number of other physical systems. Interpretation of the Talbot effect as a quantum logic operation provides a beautiful and interesting way to visualize quantum computation through wave propagation and interference.

Original languageEnglish
Article number062328
JournalPhysical Review A - Atomic, Molecular, and Optical Physics
Issue number6
Publication statusPublished - 30 Jun 2015
Externally publishedYes


Dive into the research topics of 'Quantum information processing by weaving quantum Talbot carpets'. Together they form a unique fingerprint.

Cite this