Jagat Shakya

12.5 Gbit/s carrier-injection-based silicon micro-ring silicon modulators

We show a scheme for achieving high-speed operation for carrier-injection based silicon electro-optical modulator, which is optimized for small size and high modulation depth. The performance of the device is analyzed theoretically and a 12.5-Gbit/s modulation with high extinction ratio >9dB is demonstrated experimentally using a silicon micro-ring modulator.

Cascaded silicon micro-ring modulators for WDM optical interconnection

We experimentally demonstrate cascaded silicon micro-ring modulators as the key component of a WDM interconnection system. We show clean eye-diagrams when each of the four micro-ring modulators is modulated at 4 Gbit/s. We show that optical inter-channel crosstalk is negligible with 1.3-nm channel spacing.

Subwavelength confinement in an integrated metal slot waveguide on silicon

We demonstrate propagation losses of less than 0.8 dB/microm in a metal slot waveguide on silicon with a predicted confinement substantially below the optical wavelength (approximately 1.55 microm). We also show compact and efficient coupling of the high-confinement metal slot waveguide with a standard silicon dielectric waveguide with a coupling efficiency of approximately 2.5 dB per facet.

High Speed Carrier Injection 18 Gb/s Silicon Micro-ring Electro-optic Modulator

We experimentally demonstrate electrooptic modulation in silicon at 18 Gbps (NRZ) in a micro-ring of 12 micron diameter using a pre-emphasis technique. Device simulations indicate that this technique can extend the bit rate to 40 Gbps.

Compact electro-optic modulator on silicon-on-insulator substrates using cavities with ultra-small modal volumes.

We experimentally demonstrate a micron-size electro-optic modulator using a high-index-contrast silicon Fabry-Perot resonator cavity. This compact device consists of a 1-D cavity formed within a single mode silicon channel waveguide and an embedded p-i-n junction on a silicon-oninsulator platform. The entire device is 6.0 microns in length. We demonstrate modulation depths as large as 5.87 dB at speeds of 250 Mbps limited only by fabrication imperfections, with optimized theoretical speeds of several Gbps.

Direct measurement of tunable optical delays on chip analogue to electromagnetically induced transparency

Direct time-domain measurement of tunable optical delay in a silicon resonating structure is presented. The structure is composed by a double-ring resonator, whose spectrum has a narrow transparency peak with low group velocity analogous to that in electromagnetically induced transparency. Effective group indices from 90 to 290 are obtained by tuning the resonator thermally. The measurements agree well with the theoretical analysis.

Error-free transmission of microring-modulated BPSK

We demonstrate the generation of error-free binary-phase-shift-keyed (BPSK) data at 5 Gb/s using a silicon microring modulator. The microring-modulated BPSK signal is propagated at fiber lengths up to 80 km, maintaining error-free performance, while demonstrating resilience to chromatic dispersion. Bit-error-rate measurements and eye diagrams show near equivalent performance of a microring-based BPSK modulator as compared to commercial LiNbO₃ phase modulators.

Compact Electro-Optic Modulator on Silicon-on-Insulator Substrates using Cavities with Ultra-Small Modal Volumes

We experimentally demonstrate an electro-optic modulator using a high-index-contrast silicon Fabry-Perot resonator. This compact high-speed device is a 1-D integrated cavity, only 4.5 lambda/n in length with an embedded p-i-n junction on a silicon-on-insulator platform

Compact silicon slot-waveguide disk resonator

We demonstrate a 20-mum-radius disk resonator based on Si/SiO2 slot-waveguide. Quality factors around 1,000 are measured. Low effective refractive index evidences light guiding in the low index SiO2 layer.

WDM Silicon Modulators Based on Micro-ring Resonators

We demonstrate experimentally cascaded silicon micro-ring modulators for WDM interconnection systems. We show clean eye-diagrams when each of the four micro-ring modulators coupled to a single waveguide is modulated at 4 Gbit/s