single mode laser diodeS

Precision Light Sources for High-Performance Applications

Single mode laser diodes operate on a single transverse resonator mode, delivering a highly focused and coherent light output. These laser diodes are essential in applications requiring precision and stability, such as laser surface profilers, laser position sensors, optical tweezers, and pump lasers.

A common type of single mode laser diode is the Fabry-Perot laser, known for its simple design and broad wavelength emission. Named after the Fabry-Perot interferometer, this semiconductor laser consists of a gain medium, typically made of gallium arsenide (GaAs), sandwiched between two reflective surfaces. These surfaces, often formed by cleaved semiconductor facets, create a natural optical resonator. This resonator allows light to bounce back and forth within the cavity, selectively amplifying specific wavelengths.

The core components of a Fabry-Perot single mode laser diode include:

Active Region (Gain Medium): This is where electron-hole recombination occurs, generating photons. The active region, made of GaAs, is the heart of the laser diode.
Reflective Facets: The cleaved ends of the semiconductor material act as mirrors with high reflectivity, forming the resonant cavity necessary for laser operation. One of these mirrors is partially transparent, allowing a portion of the light to escape as the laser output.
Electrical Contacts: These inject current into the active region, providing the energy required for photon generation and laser operation.

The Fabry-Perot cavity naturally selects certain wavelengths to resonate, depending on the length of the cavity and the refractive index of the material. Only those wavelengths that satisfy the resonance condition will be amplified effectively. However, unlike single frequency lasers, Fabry-Perot lasers typically emit light over a range of wavelengths or modes. A portion of the amplified light escapes through one of the reflective facets, producing a diffraction-limited output beam. The output of a Fabry-Perot laser is typically broader in terms of wavelength compared to more specialized single frequency lasers, making them suitable for applications that do not require extremely narrow linewidths.

Single mode laser diodes are ideal light source for laser surface profiler (scanner/ interferometer), laser position sensor, optical tweezer and pump laser. Our single mode laser diodes are available in compact and low cost TO9, free space butterfly window with beam collimation and TEC, single mode PM fiber output butterfly with TEC and compact flatpack window package. Available wavelengths are 808 nm (up to 800 mW cw, single emitter), 850 nm (100 mW), and 1060 nm (up to 750 mW cw, single emitter).

The 400 mW single mode fiber pump at 808 nm provides the highest power delivery in the market from a single mode polarization maintenance fiber. This allows easy application in combination with fiber switches and combiners. Further wavelength selection and locking can be realized with FBG. Please don’t hesitate to contact us for more information.