Raman
Raman is a molecular spectroscopy technique that can provides chemical and structural fingerprint information for a wide range of samples, including for example nanomaterials, polymers, powders, liquids or cells/tissues. Key Raman techniques include:
FURTHER READING ON RAMAN
- Spontaneous and stimulated
- Surface Enhanced Raman Spectroscopy (SERS)
- Surface Offset Raman Spectroscopy (SORS)
- Tip-Enhanced Raman Spectroscopy (TERS)
- Coherent Anti-Stokes Raman Scattering (CARS)
Further Reading
Technical note: Introduction to Raman Spectroscopy
App Note: Diagnosis of skin tumors during micrographic surgery
App Note: Probing Molecular Structure with Raman Spectroscopy
Luminescence
Luminescence spectroscopy is used for a large variety of applications including for example the study of metal complexes, organic LEDs (OLEDs), quantum dots, cell dynamics, stand-off detection of chemical compounds (e.g. explosives) or scintillators properties measurement. Key techniques include:
FURTHER READING ON LUMINESCENCE
- Fluorescence
- Photoluminescence
- Cathodoluminescence
- Chemiluminescence
Further Reading
App Note: Determination of Fluorescence Lifetimes using TRLFS
App Note: Characterization of Single Quantum Wires
App Note: Magneto-Photoluminence in Si Nanocrystals
Absorption / Transmission / Reflection
Ultraviolet Visible Near-Infra red (UV-Vis-NIR) spectroscopy is useful to characterise the absorption, transmission, and reflectivity of a variety of materials such as pigments, biological, coatings, windows, filters, or analyse the dynamics of chemical reactions. Variations of these spectroscopy techniques include:
FURTHER READING ON ABSORPTION
- Transient absorption (pump/probe)
- Diffuse Reflectance
Further Reading
Tech Note: Intro to Absorption, Transmission & Reflection
App Note: Spectral Response of Glucose
OES and LIBS
Optical Emission Spectroscopy (OES) is a fundamental, non-invasive
diagnostic technique for a wide range of plasma, and can provide information such as composition and species temperature and energy distribution.
FURTHER READING ON OES AND LIBS
Laser-induced breakdown spectroscopy (LIBS) is used to determine the elemental composition of various solids, liquids and gases. A high power laser pulse is focused on to a sample to create a plasma. Emission from the atoms and ions in the plasma is collected and analysed by a spectrograph and gated detector to determine the elemental composition or the elemental concentrations in the sample.
Further Reading
Case Study: Automated 2D elemental mapping by LIBS
Case Study: Stand-off LIBS
Webinar: Basic Principles of LIBS
Micro-Spectroscopy
Micro-spectroscopy covers a very wide range of spectroscopy modalities with the common character that the spectroscopic measurement is made on the microscopic scale. Andor spectroscopy systems are routinely used for Raman-based techniques including:
FURTHER READING ON MICRO-SPECTROSCOPY
- Micro- Raman and Fluorescence/Photoluminescence
- Diffuse Scattering micro-spectroscopy
- Multiphoton micro-spectroscopy
Further Reading
Tech Note: Modular Solutions for Micro-Spectroscopy
App Note: Micro-Spectroscopy as a Diagnostic Aid to Skin Cancers
Webinar: Research From Novel Nano-Devices To Clinical Diagnosis
Non-Linear Spectroscopy
Non-linear (NL) spectroscopy encompasses a number of optical techniques that can be used to study for example interfacial and surface processes, ultrafast dynamic processes (pump-probe technique), light transport or assist in the understanding of nanoparticles/nanostructures unique optical properties. Key techniques include:
FURTHER READING ON NL SPECTROSCOPY
- Second harmonic generation (SHG) spectroscopy
- Sum-frequency generation (SFG) spectroscopy
- Pump-probe transient absorption
- Coherent Anti-Stokes Raman Scattering (CARS)
Further Reading
App Note: Spectral Characterization of Quantum Light
App Note: Nearfield Spectroscopy of a ZnO Thin Film
Material Science
Optical spectroscopy can provide analytical information on materials from the micro to the nano-scale, through a number of techniques with a large range of sensitivity, resolution and flexibility requirements.
Examples include:
FURTHER READING ON MATERIAL SCIENCE
- Quantum dots
- Carbon nanotubes
- Nanowires
- Organic LEDs (OLEDs)
- Thin films
- Scintillators
- Powder/explosives
Further Reading
App Note: Chemical Analysis of Nanostructures by TERS
App Note: Nearfield Spectroscopy of a ZnO Thin Film
Chemical Processes
Optical spectroscopy can be used to non-invasively study the changes in the composition of chemical(s)
or material(s).
FURTHER READING ON CHEMICAL PROCESSES
Chemical reaction products or transient behaviours can be probed by Andor Spectroscopy systems through a variety of techniques based on Raman, transient absorption / pump-probe or fluorescence.
Further Reading
App Note: Quantitative Monitoring of Biphasic Reactions
App Note: Reaction Monitoring using UV-Resonance Raman
App Note: Reaction monitoring using SWIR Raman Spectroscopy
Life Science - Biomedical
Optical spectroscopy can provide very specific analytical information in a non-invasive matter for a range of bio-samples, often as a complement to microscopy imaging (micro-spectroscopy) or visual inspection.
FURTHER READING ON LIFE SCIENCE
Field of applications include for example cancer cell in vivo and ex vivo screening and cancer diagnostics, non-invasive monitoring of patient bio-parameters or cell sorting.
Further Reading
App Note: Identification of Lung Cancers
App Note: Diagnosis of skin tumors during micrographic surgery
App Note: Optical Spectroscopy in Biomedical research
Plasma Studies
Plasmas can be artificially produced by different means (e.g. laser ablation, coupling of capacitive / inductive power source to ionised gas). The understanding of their properties and dynamics is relevant to a number fields such as fusion, thin films deposition, micro-electronics, material characterization, display systems, surface treatment, fundamental physics, environmental & health.
FURTHER READING ON PLASMA STUDIES
Gated detectors can be used to determine optical parameters from which fundamental plasma properties can be derived. Accurate nanosecond-scale gating of image intensifier-based detectors can be used to sample plasma dynamics, or to isolate the useful plasma information generated by pulsed lasers.
Further Reading
App Note: PLIF as a Plasma Diagnostic
App Note: Broadband Cavity-enhanced Absorption Spectroscopy
App Note: Thomson Scattering