We consider an integrated electro-absorption modulator within a coupled-cavity VCSEL structure (EAM-VCSEL). We derive expressions for the modulation transfer function (MTF) of the EAM-VCSEL for small-signal modulation of either VCSEL injection current or EAM losses. For current modulation. the cut-off frequency remains limited by relaxation oscillation frequency. https://thebrickes.shop/product-category/verde-frame/