Heralded generation of single photons in pure quantum states

Lijian Zhang, Christoph Söller, Offir Cohen, Brian J. Smith, Ian A. Walmsley

Research output: Contribution to journalArticlepeer-review


Sources of single photons in pure quantum states are essential to many quantum optics applications. We explore a technique, known as group-velocity matching, that enables the heralded generation of pure single photons through nonlinear optical processes. It reduces or eliminates the requirement of spectral filtering that conventional sources rely on to achieve high purity, therefore increasing both heralding efficiency and photon flux. Implementation in both spontaneous parametric downconversion and spontaneous four-wave mixing is studied as we discuss several recent experimental realizations demonstrating purity of more than 0.84 for the heralded photons.

Original languageEnglish (US)
Pages (from-to)1525-1537
Number of pages13
JournalJournal of Modern Optics
Issue number17
StatePublished - 2012
Externally publishedYes


  • nonlinear and ultrafast optics
  • quantum optics
  • single-photon source

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics


Dive into the research topics of 'Heralded generation of single photons in pure quantum states'. Together they form a unique fingerprint.

Cite this