Hamamatsu L12004-2190H-C DFB Continuous-Wave Quantum Cascade Laser

Overview

The Hamamatsu L12004-2190H-C is a distributed feedback (DFB) continuous-wave quantum cascade laser engineered for high-stability, narrow-linewidth mid-infrared emission at a nominal wavelength of 4.57 µm. Unlike conventional interband semiconductor lasers, QCLs operate on intersubband transitions within the conduction band of engineered quantum-well heterostructures—enabling precise, room-temperature-compatible emission in the 4–10 µm spectral region where fundamental vibrational absorption bands of numerous trace gases (e.g., CO, NO, N₂O, CH₄, NH₃, and volatile organic compounds) reside. This device is fabricated using molecular beam epitaxy (MBE)-grown InP-based active regions and integrated with a monolithic DFB grating to ensure single-mode operation without external cavity stabilization. Its hermetically sealed HHL package incorporates thermoelectric cooling (TEC), precision temperature monitoring via integrated thermistor, and low-noise current drive interfaces—making it suitable for integration into portable or benchtop gas sensing platforms requiring long-term wavelength stability and minimal mode hopping.

Key Features

• DFB architecture ensures inherent single-longitudinal-mode (SLM) emission with side mode suppression ratio ≥25 dB
• Continuous-wave operation with minimum optical output power of 20 mW at 4.57 µm under optimized thermal and current conditions
• Narrow spectral linewidth ≤0.2 cm⁻¹ (FWHM), enabling high-resolution absorption spectroscopy applications
• Wavelength tunability of ±1.0 cm⁻¹ via injection current modulation—compatible with wavelength-scanned direct absorption or wavelength modulation spectroscopy (WMS)
• Operating temperature range of 10–50 °C for the QCL chip, supported by integrated TEC and thermistor feedback loop
• HHL (hermetic high-power laser) package provides mechanical robustness, electrical shielding, and thermal management for industrial and field-deployable systems
• Designed for OEM integration: standardized electrical interface, compact footprint (dimensions provided per datasheet), and compatibility with industry-standard laser drivers and temperature controllers

Sample Compatibility & Compliance

The L12004-2190H-C is optimized for use in extractive and open-path gas analysis configurations where mid-infrared light interacts with gaseous samples in multipass cells (e.g., White or Herriott cells) or photoacoustic detection modules. Its 4.57 µm emission targets the ν₁+ν₃ asymmetric stretch band of carbon monoxide (CO) and overlapping features of formaldehyde (HCHO) and nitric oxide (NO). The device complies with IEC 60825-1:2014 for Class 3B laser safety when operated within specified current and temperature limits. It supports GLP/GMP-aligned system integration through deterministic thermal and current control protocols, and its stable single-mode output facilitates traceable calibration against NIST-traceable gas standards. While the laser itself is not certified to ISO 13485 or FDA 21 CFR Part 11, its design enables compliant integration into analyzers meeting those regulatory frameworks when paired with appropriate system-level audit trails and electronic record controls.

Software & Data Management

The L12004-2190H-C operates as a hardware component within larger analytical platforms; it does not include embedded firmware or onboard software. Integration is achieved via analog current control inputs (0–2 V or 0–10 V) and digital temperature setpoint interfaces compatible with standard PID controllers (e.g., Thorlabs TED200C, Wavelength Electronics LDTC0520). Users typically implement wavelength scanning and data acquisition using third-party software environments such as LabVIEW, MATLAB, or Python-based instrument control libraries (e.g., PyVISA, NI-DAQmx). When deployed in regulated environments, full audit trail functionality—including timestamped current/temperature settings, power monitor readings, and environmental logs—must be implemented at the system level. Hamamatsu provides comprehensive operating manuals, pinout diagrams, and spectral characterization reports (including wavelength vs. current/temperature maps) to support method development and validation documentation.

Applications

• Industrial process monitoring: real-time CO concentration measurement in combustion exhaust, semiconductor fabrication cleanrooms, and chemical synthesis reactors
• Environmental air quality networks: ground-based and mobile-platform detection of urban pollutants with sub-ppb detection limits using second-harmonic WMS
• Medical breath analysis research: non-invasive detection of biomarkers such as NO (asthma inflammation indicator) and CO (hemolysis marker)
• Security and defense: standoff detection of explosive vapors and toxic industrial chemicals via backscattered IR signatures
• Fundamental spectroscopy: laboratory studies of line broadening mechanisms, pressure shifts, and isotopic selectivity in gas-phase molecular physics
• OEM instrumentation: core excitation source for FTIR accessories, quantum cascade laser absorption spectrometers (QCLAS), and photoacoustic spectroscopy modules

FAQ

Is the L12004-2190H-C compatible with standard laser drivers?
Yes—it accepts analog voltage input for current control and supports common TEC driver interfaces; however, optimal performance requires low-noise, high-stability drivers with sub-mA current resolution and milli-Kelvin temperature regulation.
Does Hamamatsu provide wavelength calibration certificates?
Hamamatsu supplies spectral characterization data sheets including measured wavelength vs. current/temperature curves; NIST-traceable calibration is performed at the system level by end-users or certified metrology labs.
Can this laser be pulsed?
No—the L12004-2190H-C is specifically designed for continuous-wave operation; for pulsed applications, Hamamatsu offers separate gain-switched or externally modulated QCL modules.
What is the expected lifetime under recommended operating conditions?
Based on accelerated life testing, median operational lifetime exceeds 10,000 hours at 20 mW output and 25 °C heatsink temperature, assuming proper electrostatic discharge (ESD) protection and thermal management.
Is fiber coupling available for this model?
The standard HHL package is free-space output; fiber-coupled variants (e.g., with polarization-maintaining or hollow-core fibers) are available as custom OEM options upon request.