Performance characteristics of phase-change integrated silicon nitride photonic devices in the O and C telecommunications bands
Joaquín Faneca, Santiago Carrillo, Emanuele Gemo, Carlota Ruíz de Galarreta, Thalía Domínguez Bucio, Frédéric Y. Gardes, Harish Bhaskaran, Wolfram H. P. Pernice, C. David Wright, Anna Baldycheva
Abstract
The evaluation and comparison of the optical properties in the O and C bands of silicon nitride rib waveguides with integrated Ge 2 Sb 2 Te 5 phase-change cells is reported. In straight rib waveguides, a high transmission contrast is observed in both bands when the Ge 2 Sb 2 Te 5 cell is switched between states, being up to 2.5 dB/ μ m in the C-band and 6.4 dB/ μ m in the O-band. In the case of silicon nitride ring resonator waveguides, high quality factor resonances ( Q ∼ 10 5 ) are found in both bands, leading to the provision of an ON-OFF switch characterized by an extinction ratio of 12 and 18 dB in O and C bands respectively. Finally, with the view to provide a comparison of the wavelength-dependent optical switching of the phase-change cell, a 3-dimensional finite-element method simulation is performed and a comparison of the optical-to-thermal energy conversion in both bands given.