| Crystal | Process | PM Type | Tuning Method | SNLO Example Use Case | |---------|---------|---------|----------------|------------------------| | BBO | SHG 800→400 nm | Type I (ooe) | Angle (29°) | High-energy pulsed lasers | | LBO | SHG 1064→532 nm | Type I (ooe) | Non-critical (90°) | High average power, low walk-off | | KTP | OPO 532 nm pumped | Type II (eoe) | Angle or temperature | Nanosecond OPOs | | PPLN | DFG 1.5 μm & 1.06 μm → 3.5 μm | QPM (1st order) | Temperature | Mid-IR CW generation |
SNLO (by A. V. Smith, AS-Photonics) is a widely used tool to design and analyze these processes. Typical processes include:
| Process | Acronym | Input → Output | |---------|---------|----------------| | Second Harmonic Generation | SHG | ω + ω → 2ω | | Sum Frequency Generation | SFG | ω₁ + ω₂ → ω₃ | | Difference Frequency Generation | DFG | ω₁ – ω₂ → ω₃ | | Optical Parametric Generation | OPG | ω_pump → ω_signal + ω_idler | | Optical Parametric Amplification | OPA | ω_pump + ω_weak seed → amplified ω_s + ω_i |
SNLO calculates: phase matching angle, walk-off, gain, conversion efficiency, spectral bandwidth, and temperature tuning. crystal nonlinear optics with snlo examples pdf
SNLO allows you to compute phase-matching angles and spectral bandwidths for all these types across over 40 common crystals.
Several university labs and photonics companies provide pre-made SNLO example PDFs. Search for:
However, note that full PDF textbooks on SNLO are rare; most are slide sets or short guides. The most valuable PDFs are those you create from your own simulations. | Crystal | Process | PM Type |
Goal: Design a visible-pumped OPA: 400 nm pump → signal (600–700 nm) + idler (900–1100 nm).
SNLO Steps:
Key Outputs:
Takeaway: SNLO’s tuning plots help select crystal angle for desired signal wavelength.
When selecting a crystal for an SNLO simulation, you need:
| Parameter | Symbol | Importance | |-----------|--------|-------------| | Transparency range | - | Determines usable wavelengths | | Sellmeier equations | ( n^2(\lambda) = A + \fracB1 - C/\lambda^2 + \fracD\lambda^2 ) | Refractive index vs. wavelength | | Nonlinear coefficient | ( d_\texteff ) (pm/V) | Conversion efficiency | | Angular and temperature bandwidth | ( \Delta\theta L ), ( \Delta T L ) | Tolerance to misalignment | | Walk-off angle | ( \rho ) | Spatial beam separation | SNLO allows you to compute phase-matching angles and
SNLO example (SHG, Type I, 1064 nm → 532 nm):