Polarization Maintaining Cable

Polarization-Maintaining Fiber (PM Fiber) is a specialized optical fiber designed to maintain the polarization state of light propagating through it. Unlike standard singlemode fibers, which randomly scatter polarization due to imperfections and external stresses, PM fibers are engineered to preserve a linear polarization state over long distances.

The PM Fiber Cable are widely used in polarization sensitive fiber optical systems for transmission of light that requires the PM state to be maintained. All the Pm maintaining cable from FiberMart meet or exceed industry standards for applications where polarization sensitivity is a requirement. Our High extinction ratio Pm cable, PM fiber pigtails comes in many flexible configurations, with choice of connectors, like FC/UPC, FC/APC, SC/UPC, SC/APC and LC connectors are available in 460nm, 630nm, 780nm, 980nm, 1310nm, 1550nm wavelengths. Polarization Maintaining Cable for sale, 250µm bare fiber, 900µm buffered fiber or 3mm cable can be supplied in any lengths. Buy PM cable, PM Fiber Patchcord from Fiber-MART.COM with free shipping, ISO9001 qualified in stock!

Introduction

Polarization Maintaining Fiber Cable, also known as PM Cable, is a specialized type of fiber optic cable designed to preserve the linear polarization state of light as it travels through the fiber. In standard single-mode fibers, the polarization state is unstable and can vary randomly due to external stresses and imperfections. PM cables overcome this by introducing a permanent, controlled asymmetry (high birefringence) within the fiber core. This is essential for applications where the polarization of light is critical to the system's functionality and performance.

Features

● Stable Polarization State: Maintains a consistent linear polarization orientation over long distances and under varying environmental conditions.

● Low Polarization Crosstalk: High extinction ratio ensures minimal mixing or coupling between two orthogonal polarization modes.

● High Polarization Extinction Ratio (PER) Typical > 23dB, Low Insertion Loss < 0.2dB, Ensures highly stable output polarization with minimum fiber loss.

● Precision Alignment: Connectors (like FC/APC) are typically keyed and aligned Slow Axis, Fast Axis or Both Axis Working, to ensure proper polarization orientation.

● High Quality Certificated with CE, RoHS, FCC. Individual Testing Report Included for Each Unit with Life-time Warranty. 

Principle

The core principle is based on creating high birefringence within the fiber. This is achieved by introducing asymmetric stress-applying parts (e.g., elliptical cladding, or stress rods as in Panda and Bow-Tie fibers) around the core during manufacturing. This asymmetry creates two distinct, stable propagation paths (fast axis and slow axis) for light with different polarization orientations. When light is launched into one of these principal axes, the strong birefringence prevents power from coupling to the orthogonal axis, thereby "locking in" the input polarization state along the entire fiber length.

Applications

● Fiber Optic Sensing: Interferometric sensors (gyroscopes, hydrophones, current sensors) where phase information is key.

● Coherent Optical Communications: Systems using advanced modulation formats that encode information in the polarization state.

● Quantum Communication & Computing: For transmitting polarization-encoded qubits.

● Nonlinear Frequency Conversion: Processes like second harmonic generation (SHG) in fibers, which are polarization-dependent.

● Pumped Laser Systems: Especially for fiber lasers and amplifiers where the pump light requires a specific polarization state.

● Research & Laboratory Setups: Any experiment or measurement system where controlling light polarization is critical.

Specifications