Terahertz absorption and refractive index
transmission or reflection
Material Analysis · Structure & Spectroscopy
Terahertz Time-Domain Spectroscopy (THz-TDS)
Characterise terahertz absorption and refractive index, complex permittivity and conductivity, and layer thickness, defects, or carrier dynamics using a scope agreed around your sample and decision.
- Price
- from£60 per sample, excl. VAT
- Turnaround
- 8 working days Preparation and scope dependent
- Available platforms
- Menlo Systems TERA K15Toptica TeraFlash smart
- Typical outputs
- Time-domain waveformFrequency-domain amplitude and phaseOptical constants, conductivity, thickness, or tomographic viewsProcessed spectra
Why this service
What THz-TDS can help you understand
Terahertz Time-Domain Spectroscopy is selected when the project needs defensible information on terahertz absorption and refractive index, complex permittivity and conductivity, or layer thickness,…
Complex permittivity and conductivity
imaging/tomography
Layer thickness, defects, or carrier dynamics
temperature, pump-probe, or polarisation measurements
Choose the scope
Start from the question, not the tool
The method, preparation route and reporting depth depend on what you need to decide.
Transmission or reflection
terahertz absorption and refractive index
- Best used when
- terahertz absorption and refractive index
- Typical result
- Time-domain waveform
- Preparation note
- State the substrate, nominal thickness and whether sectioning or mounting is permitted.
Imaging/tomography
complex permittivity and conductivity
- Best used when
- complex permittivity and conductivity
- Typical result
- Frequency-domain amplitude and phase
- Preparation note
- Gas compatibility, fittings, flow and safety controls are confirmed before acceptance.
Temperature, pump-probe, or polarisation measurements
layer thickness, defects, or carrier dynamics
- Best used when
- layer thickness, defects, or carrier dynamics
- Typical result
- Optical constants, conductivity, thickness, or tomographic views
- Preparation note
- Confirm dimensions, cutting permission and whether the original geometry must be preserved.
Common outputs
A result package matched to the decision you need to make
Fields, conditions, processing and file formats are confirmed before work begins.
Time-domain waveform reported with the agreed units, sample reference and measurement conditions.
Frequency-domain amplitude and phase supplied in a labelled format suitable for direct sample or condition comparison.
Optical constants, conductivity, thickness, or tomographic views provided with the processing basis and quality checks agreed during technical review.
Processed spectra included when selected in the confirmed reporting scope.
Example results
What THz-TDS results can look like
The image shows schematic diagram of the terahertz time-domain spectroscopy system.
Research source · source · CC BY
The plot shows time-domain terahertz pulses of 50 μm and 100 μm length dipole antenna and the corresponding Fourier-transformed spectra.
Research source · source · CC BYSample requirements
What to provide before work begins
Provide representative, clearly labelled samples and identify the decision, feature or comparison that matters.
| Suitable sample | Submission requirement | Planning note |
|---|---|---|
| Film / coating | Provide the coated substrate or a flat film with the test surface and coating side clearly marked. | State the substrate, nominal thickness and whether sectioning or mounting is permitted. |
| Gas / headspace | Provide the gas composition, concentration range, cylinder or sampling format and required pressure. | Gas compatibility, fittings, flow and safety controls are confirmed before acceptance. |
| Solid / component | Provide a clean, stable and clearly labelled specimen with the target face or region identified. | Confirm dimensions, cutting permission and whether the original geometry must be preserved. |
Objective: state the decision, comparison or acceptance criterion the work must support.
Handling and access: declare hazards, instability, confidentiality, file constraints or special logistics before dispatch or transfer.
Questions and answers
Common planning decisions
Short answers to issues that can change preparation, scope, timing or interpretation.
What should I send for Terahertz Time-Domain Spectroscopy?
Provide film / coating, gas / headspace, solid / component as applicable. Exact quantity, dimensions and preparation are confirmed during technical review.
Which analysis option should I choose?
Choose the mode around the decision you need to make. For terahertz absorption and refractive index, start with transmission or reflection; add imaging/tomography when comparison or quantification is required.
How long will the test take?
Typical turnaround is 8 working days after sample acceptance and method confirmation.
What can limit the result?
Water, metals, and highly absorbing samples limit penetration. Multiple reflections and thickness uncertainty affect optical-constant extraction.
Configure the service
Send the information needed to scope THz-TDS correctly
- Sample form, material, dimensions and quantity
- Feature or decision the result must address
- Required comparison, acceptance criterion or reference
- Preferred output and reporting depth