1 December 2024

Broad Spectrum (200 – 2200 nm) High-Resolution Raman and Photoluminescence Measurement System (Optical Characterization)

This optical characterization system is capable of performing both Raman and photoluminescence (PL) measurements across a broad spectral range of 200 to 2200 nm. It is designed for advanced research and characterization of materials, providing detailed insights into their molecular and electronic properties.

Photoluminescence (PL) Measurement:

Photoluminescence is based on the principle where a material absorbs light at a specific wavelength, elevating it to a higher energy state, and then releases photons as it returns to its ground state. The collected photons’ wavelength and intensity provide information about the material’s characteristic properties.

Raman Measurement:

In Raman measurement, the laser light incident on a sample interacts with the molecules of the material, causing a small number of photons to scatter at a different wavelength. This phenomenon, known as Raman scattering, results in a shift in the frequency of the light, referred to as the Raman Shift. The Raman shift provides valuable information on the sample’s chemical bonds, bond structures, bond lengths, molecular vibrations, rotational modes, phase state, chemical composition, stress, and deformations, as well as the effects of environmental factors like temperature and pressure.

System Features:

• Motorized Compartment for Micro Raman and Photoluminescence Measurements: Compatible with microscope and multi-laser system-based micro Raman and photoluminescence measurements.
• Microscope Body: Capable of holding at least 7 objectives. Available objectives include:
  • 10x (working distance of at least 6.5 mm)
  • 50x (working distance of at least 8.2 mm)
  • 100x (working distance of at least 2.0 mm)
  • Vertical type microscope head for cold head systems.
• Macro Lens: 25 mm fused silica macro lens.
• Laser and Optical Sources:
  • 30 mW optical output, 325 nm wavelength linear polarized He-Cd Laser.
  • 100 mW optical output, 532 nm wavelength diode-pumped solid-state laser.
  • 100 mW optical output, 785 nm wavelength stabilized single-mode diode laser.
• Spectral Range for Raman and PL:
  • Photoluminescence Spectral Range: 200 – 2200 nm.
  • Raman Spectral Range: 200 – 2200 nm.
• Raman Spectrometer Configuration:
  • Spectrograph with a minimum focal length of 750 mm.
  • Raman shift resolution: 0.3 cm–1 to 1 cm–1.
  • Minimum f/9.8 aperture.
  • 532 nm for 60 cm-1 Raman shift range, and 325 nm PL for Raman shift bands.
• Detectors:
  • CCD Detector:
    • Spectral range: 200 – 1050 nm.
    • Pixel format: 2000 x 256 pixels.
    • Active area: 30 x 3.8 mm.
    • Dark current: 0.1e-/pix-second, with quantum efficiency of 95%.
  • InGaAs Detector:
    • Spectral range: 1000 – 2200 nm.
    • Thermoelectrically cooled InGaAs array detector.
    • Pixel format: 2000 x 256 pixels.
    • Active area: 30 x 3.8 mm.
    • Dark current: 0.1e-/pix-second, with quantum efficiency of at least 70%.
• Mapping Capabilities:
  • XYZ motorized stage with a step resolution of at least 100 nm, capable of moving at least 75 mm x 55 mm in the XY axis.
  • Stage step controller with a stage joystick for easy control.
• Low-Temperature Unit:
  • Dual-stage cold head with a high-power 50 Ohm resistance heater.
  • He compressor for cooling.
  • Temperature control using a digital controller with multiple temperature sensor inputs and PID loop control, allowing for precise control from 0.1 K/min to 100 K/min heating speed.
• Vacuum System:
  • Two-stage rotary vane oil mechanical pump with a vacuum range of 2 x 10^-3 mbar and a maximum transport capacity of 200 L/min at 50 Hz.

This system provides an advanced solution for characterizing material properties across a wide spectral range, offering high sensitivity, accuracy, and versatility in research applications related to materials science, nanotechnology, and optoelectronics.