Ultra-Narrow Linewidth Single-Frequency Fiber Laser

The ultra-narrow linewidth single-frequency fiber laser is designed for applications requiring Hz-level or sub-kHz spectral linewidth, very long coherence length, and extremely low phase noise. It is widely used in long-range measurements, coherent detection, precision laboratory experiments, and advanced optical system integration where spectral purity and frequency stability directly determine system performance.

What Is an Ultra-Narrow Linewidth Fiber Laser?

An ultra-narrow linewidth fiber laser is engineered to achieve extremely low linewidth levels, often in the Hz or sub-kHz range. Linewidth represents the laser's spectral purity, and a narrower linewidth means minimal frequency fluctuations over time. This improves phase stability and greatly extends coherence length, making these lasers suitable for advanced optical systems that demand stable frequency control, such as coherent detection, quantum research, and high-precision sensing.

Why Linewidth Matters in High-Precision Applications

• Longer coherence length for long-range and high-resolution interferometry
• Improved phase noise characteristics for sensitive coherent detection
• Higher measurement accuracy in metrology and optical sensing
• Superior performance in interferometric and heterodyne systems
• Stable long-range signal transmission over optical fiber links

Key Features of Hz-Level Ultra-Narrow Linewidth Fiber Lasers

• Spectral stability from ultra-stable cavity design and locking techniques
• Extremely long coherence length suitable for kilometer-scale interferometers
• Low phase noise optimized for coherent communication and RF generation
• All-fiber architecture for compact, alignment-free, and robust integration
• Available at 1550 nm, 1064 nm and custom wavelength ranges

Understanding Single-Frequency Operation

The single-frequency fiber laser design restricts emission to a single longitudinal mode, ensuring a spectrally pure, stable output. When combined with ultra-narrow linewidth, the result is exceptional stability in both frequency and phase. This is essential for systems where even slight frequency deviations can create measurement errors, degrade interference contrast, or reduce coherent detection performance.

1550 nm Narrow Linewidth Source for Advanced Systems

1550 nm is one of the most widely used wavelength bands in optical fiber communication, coherent LIDAR, and atmospheric research. The 1550 nm region offers low fiber attenuation, high eye safety, and compatibility with telecom-grade components. A Hz-level ultra-narrow linewidth laser at 1550 nm is ideal for long-distance coherent transmission, high-resolution ranging, and advanced sensing applications that require stable, low-noise optical sources.

Representative Application Areas

• Coherent detection and coherent LIDAR systems
• Optical frequency domain reflectometry and distributed fiber sensing
• Fiber optic gyroscopes (FOG) and inertial navigation systems
• Distributed acoustic and strain sensing over long fiber spans
• Atomic physics, cold atom trapping, and quantum optics experiments
• Microwave photonics for low-noise RF and microwave signal generation

Technical Advantages of Hz-Level Narrow Linewidth Lasers

• High spectral purity and ultra-low phase noise
• Exceptional coherence for long-range interferometry and sensing
• Compatibility with isolators, modulators and coherent receivers
• Thermally stabilized design for minimal wavelength drift
• Engineered for continuous operation with low maintenance requirements

Product Specifications Overview

Typical performance parameters for ultra-narrow linewidth fiber lasers include Hz to sub-kHz linewidth, output power options from milliwatts to watt-level, standard wavelengths such as 1550 nm and 1064 nm with additional custom ranges, high frequency stability optimized for long-term operation, and PM or SM fiber output formats. Optional modules such as integrated isolators, amplifiers, and frequency-locking electronics can be provided based on specific project requirements.

Laser Architecture and Design Principles

The laser architecture is based on an ultra-stable resonant cavity combined with high-precision fiber Bragg gratings for wavelength selection and spectral filtering. Advanced temperature control minimizes thermal drift, while noise-suppression strategies reduce frequency jitter and phase noise. Combined, these design choices deliver the performance required for cutting-edge coherent systems, quantum experiments, and high-precision sensing platforms.

Integration Options and System Compatibility

Ultra-narrow linewidth laser models can be configured with frequency-locking electronics, external modulators, fiber amplifiers, coherent receivers, and interferometric measurement equipment. This flexibility enables system designers to integrate the lasers into a wide range of applications—from laboratory benches and testbeds to OEM modules and field-deployed sensing systems—while maintaining high performance and reliability.

Quality, Reliability, and Manufacturing Standards at Techwin

Each ultra-narrow linewidth fiber laser is manufactured using strict precision assembly, advanced optical engineering tools, and rigorous testing. Products undergo noise testing, spectral purity analysis, thermal stability checks, and long-term operation evaluation. Facilities in Hangzhou City support modern production standards to ensure high reliability, long working life, and dependable optical performance for scientific, industrial, and metrology customers.