Auniontech 1550 nm Type-II Polarization-Frequency Entangled Photon Pair Source

Overview

The Auniontech 1550 nm Type-II Polarization-Frequency Entangled Photon Pair Source is a benchtop quantum optical instrument engineered for high-fidelity generation of polarization- and frequency-entangled photon pairs in the telecom C-band. It leverages spontaneous parametric down-conversion (SPDC) in a temperature-tuned periodically poled lithium niobate (PPLN) waveguide under quasi-phase-matching (QPM) conditions. Operating at 1550 nm—aligned with low-loss transmission windows in standard single-mode fiber and compatibility with silicon-based detectors—the source delivers >250,000 entangled photon pairs per second with ≤5 mW pump power. Its compact architecture integrates a wavelength-stabilized pump laser, thermally regulated PPLN crystal, and polarization-maintaining fiber coupling into a robust, alignment-free platform. Designed for deterministic operation at room temperature, it eliminates cryogenic requirements while maintaining long-term phase stability (<20 pm drift) and high spectral purity (<2 nm FWHM bandwidth). This enables reliable deployment in quantum communication testbeds, quantum metrology labs, and integrated photonic characterization environments.

Key Features

• High-brightness entangled photon generation via Type-II SPDC in QPM-engineered PPLN waveguide
• Simultaneous polarization and frequency entanglement with >99% two-photon interference visibility
• Center wavelength tunable over ±2 nm with sub-picometer thermal resolution via precision Peltier control
• Low pump threshold: full specification achieved with ≤5 mW pump power at 775 nm
• Dual-control interface: intuitive front-panel operation and USB-connected GUI software with real-time monitoring
• Full programmability via provided DLL library supporting LabVIEW, C++, and Visual Basic for custom automation and integration into larger quantum systems
• Optimized fiber interfaces: FC/APC connectors for PM-HI780 (pump input), PM-1550 (signal/idler output), ensuring minimal coupling loss and polarization extinction ratio >20 dB

Sample Compatibility & Compliance

The source is compatible with standard telecom-grade single-mode fibers (SMF-28, PM-1550) and integrates seamlessly with industry-standard detection modules—including superconducting nanowire single-photon detectors (SNSPDs), InGaAs avalanche photodiodes (APDs), and time-correlated single-photon counting (TCSPC) systems. Its optical output meets IEC 60825-1 Class 1 laser safety requirements when operated within specified pump power limits. The device conforms to electromagnetic compatibility standards EN 55032 and EN 55035, and its firmware supports audit-ready logging for GLP-compliant quantum optics experiments. While not certified for clinical or industrial process control, its stable output and reproducible entanglement fidelity make it suitable for R&D validation under ISO/IEC 17025-accredited laboratory conditions.

Software & Data Management

The proprietary control software provides real-time visualization of pump power, crystal temperature, coincidence counts, and accidental rate metrics. All operational parameters—including setpoint temperature, pump attenuation, and acquisition duration—are logged with timestamped metadata in CSV format. The included DLL exposes low-level register access for synchronized hardware triggering and external clock synchronization (e.g., TTL input for gated detection). Software architecture supports multi-threaded acquisition and is compatible with Windows 10/11 (64-bit) and MATLAB Runtime v9.10+. For regulated environments, optional firmware upgrade enables 21 CFR Part 11-compliant electronic signatures and audit trail generation upon request.

Applications

• Quantum key distribution (QKD) system development and channel characterization over fiber links up to 300 km
• Bell inequality violation tests and quantum nonlocality demonstrations under ambient conditions
• Quantum-enhanced interferometry and dispersion-free imaging using entangled photon correlations
• Calibration and benchmarking of single-photon detectors and time-of-flight measurement systems
• Integrated photonic circuit testing, including on-chip Bell-state analyzers and reconfigurable interferometers
• Fundamental studies of quantum decoherence in telecom-band photonic channels

FAQ

What pump laser specifications are required to operate this source?
The unit is pre-aligned for use with a 775 nm, TEM₀₀, CW diode-pumped solid-state (DPSS) laser delivering ≤5 mW through PM-HI780 fiber. External pump lasers must exhibit linewidth <1 MHz and RMS power stability <0.5% over 1 hour.
Can the entanglement type be switched between polarization and time-bin?
No—this model generates fixed Type-II polarization-frequency entangled pairs via birefringent phase matching in the PPLN waveguide. Time-bin entanglement requires additional interferometric stabilization not implemented in this design.
Is remote operation supported over Ethernet or GPIB?
Native control is USB 2.0 only; however, the DLL supports wrapper implementation for TCP/IP or serial-to-USB gateways in custom integrations.
Does the source include calibration certificates traceable to NIST or PTB?
Factory calibration data (wavelength, brightness, CAR, visibility) is provided with each unit. NIST-traceable calibration is available as an optional service with lead time.
What maintenance is required during normal operation?
None beyond periodic verification of fiber connector cleanliness and ambient temperature stability. No consumables or alignment adjustments are needed within the 2-year warranty period.