Related Experiment Video
Updated: Jun 1, 2026
12:19
Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Stable single-photon interference in a 1 km fiber-optic Mach-Zehnder interferometer with continuous phase adjustment
1Center for Telecommunication Studies, Pontifical Catholic University of Rio de Janeiro, R. Marquês de São Vicente 225, Gávea, 22451-900, Rio de Janeiro, Brazil. guix@opto.cetuc.puc‑rio.br
Optics Letters
|May 20, 2011
Summary
Researchers achieved stable, adjustable single-photon interference in a 1 km fiber-optic Mach-Zehnder interferometer. This breakthrough enables quantum repeaters and Bell
Area of Science:
- Quantum optics
- Quantum information science
- Fiber optics
Background:
- Single-photon interference is fundamental for quantum information processing.
- Maintaining phase stability in long fiber-optic interferometers is challenging.
- Previous experiments lacked user-adjustable phase control for single photons.
Purpose of the Study:
- To demonstrate stable and user-adjustable single-photon interference.
- To implement a phase control system for a kilometer-long fiber-optic Mach-Zehnder interferometer.
- To achieve high single-photon visibility for quantum applications.
Main Methods:
- Utilized a 1 km fiber-optic Mach-Zehnder interferometer.
- Implemented an active phase control system with classical laser feedback.
- Employed a phase modulator synchronized with single-photon detectors and a piezoelectric fiber stretcher for phase stabilization.
Main Results:
- Achieved stable and user-adjustable single-photon interference.
- Demonstrated continuous tuning of the single-photon phase difference.
- Obtained a high single-photon net visibility of 0.97.
Conclusions:
- The developed system enables precise control over single-photon interference in long-haul fiber optics.
- This work paves the way for experimental realizations of quantum repeaters.
- It also opens possibilities for violating Bell's inequalities using energy-time entanglement.
