Parameters
Presets
Cavity Parameters
Cavity length L300 μm
Front mirror R₁0.32
Rear mirror R₂0.95
Refractive index n3.50
Gain / Loss Parameters
Internal loss αᵢ20 cm⁻¹
Material gain g₀100 cm⁻¹
Confinement factor Γ0.35
Internal QE ηᵢ0.80
Lasing wavelength λ1310 nm
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Threshold Ith [mA]
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Slope Efficiency [W/A]
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Mirror Loss αm [cm⁻¹]
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Mode Spacing [GHz]
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Q-Factor (×10⁶)
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Photon Lifetime [ps]
L-I Curve (Output Power vs Current)
Longitudinal Mode Spectrum
Key Formulas
Mirror loss:
$$\alpha_m = \frac{1}{2L}\ln\!\frac{1}{R_1 R_2}$$Threshold gain condition:
$$\Gamma g_{th} = \alpha_i + \alpha_m$$Differential quantum efficiency:
$$\eta_d = \eta_i \cdot \frac{\alpha_m}{\alpha_i + \alpha_m}$$Longitudinal mode spacing:
$$\Delta\nu = \frac{c}{2nL}$$Photon lifetime:
$$\tau_{ph} = \frac{n}{c(\alpha_i + \alpha_m)}$$
Engineering Note: Minimizing threshold current and maximizing slope efficiency are conflicting objectives. VCSEL cavities (~10 μm) have THz-scale mode spacing — effectively single-mode without a grating. High-power fiber lasers can achieve wall-plug efficiencies >30% with slope efficiencies approaching the quantum limit.