THz Time-Domain Spectroscopy & Imaging
Femtosecond drive lasers, organic-crystal / photoconductive THz emitters, EOS detection, and real-time THz cameras for 0.1 – 10 THz spectroscopy and imaging.
Step 1 — Define your goal
What are you trying to achieve?
Pick the experiment / project closest to yours. We'll route you to the right system architecture and BOM.
Step 2 — Confirm the problem
Common project challenges
If any of these sound familiar, you're in the right place. WaveQuanta engineers have seen — and solved — every one of them.
Low THz field strength → low SNR
Photoconductive emitters give µW; organic crystals (DSTMS / DAST) give kV/cm fields but need 1.5 µm pump.
Broadband detection vs spectral coverage
EOS in ZnTe → 3 THz; GaP → 7 THz; air-biased / spintronic → 30 THz. Detector choice constrains your chemistry.
Pump laser jitter and timing drift
TDS scans are sensitive to delay-line and laser CEP / timing drift over minutes.
Atmospheric water absorption
Below 3 THz, water lines kill your signal — N₂ purge or vacuum is often necessary.
Real-time imaging vs raster scanning
Pyroelectric arrays / microbolometer cameras for fast imaging; raster + EOS for spectroscopic imaging.
Pump leakage into THz channel
ITO / metallic filters / wire-grid + careful spatial filtering on the pump.
Calibration & reference traces
Vacuum / N₂ purged reference, time-base calibration, polarization characterization.
System fits on a breadboard?
TDS station: 1.2 × 0.6 m. Pump-probe + cryostat: 2 × 1 m. Fiber-coupled compact: 50 × 50 cm.
Step 3 — Understand the system
Typical system architecture
Most projects in this area follow a similar signal flow. Your specific architecture depends on resolution, throughput, and form-factor targets.
Yb / Er fiber 1030 / 1550 nm, 100–500 mW. Or Ti:sapph for legacy ZnTe-based setups.
Variable splitter, polarization control, beam routing.
Photoconductive antenna or organic crystal (DSTMS / DAST) + collimating mirror.
Mechanical delay line for time-base scanning. ≥10 ps range typical.
ZnTe / GaP electro-optic detection crystal + balanced photodiode pair.
Step 4 — Pick the modules
Recommended system modules
These are the building blocks. Each module is a category of products — pick the right brand and grade for your project stage below.
fs Drive Laser
Yb / Er fiber 1030 / 1550 nm, 100–500 mW. Or Ti:sapph for legacy ZnTe-based setups.
- Yb fiber 1030 nm · 100–300 fs
- Er fiber 1550 nm for organic-crystal pump
- Low timing jitter / CEP-stable optional
Pump / Probe Beam Splitting
Variable splitter, polarization control, beam routing.
- Polarization-controlled splitter
- λ/2 + PBS for power balance
- Compact breadboard layout
THz Emitter & Output Optics
Photoconductive antenna or organic crystal (DSTMS / DAST) + collimating mirror.
- Photoconductive antenna (PCA)
- Organic crystal DSTMS / DAST
- Off-axis parabolic THz collimator
Optical Delay Line
Mechanical delay line for time-base scanning. ≥10 ps range typical.
- Motorized delay line · 10–50 ps
- Encoder feedback for TDS
- Rapid-scan option for live spectra
EOS Detection (free-space)
ZnTe / GaP electro-optic detection crystal + balanced photodiode pair.
- ZnTe (≤3 THz) or GaP (≤7 THz)
- λ/4 + Wollaston balanced detection
- Lock-in amplifier
Real-time THz Camera
Microbolometer or pyroelectric array for live THz imaging.
- RIGI uncooled THz camera
- Frame rate ≥50 Hz
- Direct imaging or focal-plane array
FTIR / Power Meter
Broadband FTIR or pyroelectric power meter for absolute THz characterization.
- Ftirzz THz FTIR
- Pyroelectric THz detector
- Golay cell for absolute power
Optional 1.5 µm Conversion
OPA / SHG / ultrabroadband conversion for organic-crystal pump (DSTMS optimal at 1.5 µm).
- Yb → 1.5 µm OPA
- MgO:LN waveguide DFG
- Custom THz chemistry support
Step 5 — Match your project stage
Choose your project stage
Same modules, three configurations sized for where your project is today. Move up the tiers as you progress from research to validation to OEM.
Research Starter
Lab THz-TDS · spectroscopy
Standard photoconductive-antenna THz-TDS. Yb fiber pump, ZnTe / GaP EOS detection, lock-in amplifier, 0.1–3 THz with N₂ purge.
- Yb fiber 1030 nm · ≤300 mW
- Photoconductive antenna emitter
- ZnTe / GaP EOS detection
- Motorized delay line
- Lock-in amplifier
- N₂ purge enclosure
BOM tier: $80k – $180k
Engineering Validation
Pump-probe / high-field THz
Organic-crystal THz emitter (DSTMS / DAST) + 1.5 µm OPA pump → kV/cm THz fields. Real-time imaging arm + FTIR characterization.
- Yb pump + 1.5 µm OPA
- DSTMS / DAST organic crystal
- EOS + camera dual detection
- Real-time RIGI THz camera
- Ftirzz FTIR + power meter
- Cryostat-compatible mounts
- Climate-controlled enclosure
BOM tier: $300k – $700k
OEM Production
Industrial THz inspection / NDT line
Sealed industrial THz station for QC / NDT. Compact fiber-coupled or imaging-arm-only. Vibration- and humidity-tolerant.
- Sealed Yb fiber laser
- Integrated emitter + detection
- Real-time imaging camera
- Auto-calibration
- Industrial enclosure (IP-rated)
- Long-term service contract
BOM tier: $500k+ · contract
Step 6 — Run the numbers
Recommended calculators
Sanity-check your design before talking to an engineer.
Step 7 — Configure the system
Configure your setup with our engineering tools
Two ways to go from "this is what I want to do" to "this is the BOM I need".
Open THz-TDS Virtual Lab
Place fs pump, organic crystal, OAP, EOS detection, and a delay line on a 3D breadboard. Validate path lengths and export a turn-key BOM.
Launch Virtual LabAsk AI to scope my THz system
Describe your spectral coverage, sample, and field-strength target. AI Concierge proposes laser, emitter, detection, and imaging in 30 seconds.
Open AI ConciergeStep 8 — Anchor SKUs
Featured products for this application
Common picks for this application area. Your final BOM will pull from a wider catalog and be sized to your project tier.
WaveQuanta
AURORA-IR Mid-Infrared OPA · High Power
WaveQuanta
HELIOS-HE Femtosecond Laser · 20 W
WaveQuanta
RIGI XL4 Premium THz Camera
WaveQuanta
RIGI M2 THz Camera
WaveQuanta
Ftirzz THz FTIR
WaveQuanta
Mozza Mid-IR Detector
LBTek
Manual Adjustable Delay Line LBODL
LBTek
ZnSe Window — Broadband Mid-IR / THz
Step 9 — Common questions
Frequently asked questions
Quick answers to the questions our application engineers hear most often.
Which THz emitter should I pick?
Photoconductive antennas: easy, fiber-friendly, pump at 800 / 1030 nm, but low field (V/cm) and limited bandwidth (~3 THz). Organic crystals (DSTMS / DAST): kV/cm fields, broadband (0.5–8 THz), but need ~1.5 µm pump (so add an OPA). Spintronic emitters: ultrabroadband (up to 30 THz), modest field, simple optics.
ZnTe vs GaP for EOS?
ZnTe is the workhorse, phase-matched up to ~3 THz at 800 nm. GaP extends to ~7 THz but with lower signal (smaller r₄₁). For broadband, use a thin (≤100 µm) GaP. For maximum signal, use a thick (≤2 mm) ZnTe.
Do I really need vacuum / nitrogen purge?
For frequencies above 3 THz, atmospheric water lines (1.65, 2.04, 3.84 THz, etc.) eat into your spectrum. N₂ purge (down to 1% RH) restores most bands. Vacuum is needed only for ultra-high-field nonlinear measurements where small losses matter.
Why use a 1.5 µm OPA pump?
Organic crystals (DSTMS, DAST, OH1) achieve their highest THz conversion efficiency when pumped at 1.3–1.5 µm. From a 1030 nm Yb laser, you reach 1.5 µm with a single-stage OPA — the conversion is straightforward and unlocks 10× higher THz field.
Spectroscopy vs imaging — what's different?
TDS spectroscopy: focused beam, EOS detection, lock-in, delay-line scanning. Gives full complex permittivity ε(ω). Imaging: collimated / focused beam, real-time camera (microbolometer / pyroelectric), no spectral resolution unless paired with a tunable source.
Real-time THz video — how fast?
RIGI XL4 / M2 microbolometer cameras run at ≥25 fps live with sub-100-mK NETD at 1 THz. Good enough for security imaging, NDT inspection, and material screening. Spectroscopic imaging is slower (raster + TDS).
Field strength — how much can I push?
Peak fields with 1.5 µm + DSTMS reach 1–10 MV/cm in tightly focused geometries. Spintronic emitters at multi-mJ: 100s of kV/cm. PCAs: ~kV/cm. Match field to your nonlinear effect target (Bloch oscillation, Zener tunneling, etc.).
OEM-ready industrial THz station?
For inline NDT or QC: sealed Yb fiber laser + RIGI imaging arm + integrated optics + IP-rated enclosure. We've delivered turn-key OEM systems for art-conservation and pharma-coating inspection — multi-year service contracts standard.
Step 10 — Engineering Review
Application Engineering Review
Tell us your application, current setup, and project context. A WaveQuanta application engineer will return initial recommendations within 1 business day.
- 1 Application
- 2 Current setup
- 3 Project & purchase