Single Silicon Waveguide Research Articles

Single silicon waveguide MRR based Fano resonance in the whole spectral bands

Single silicon waveguide MRR based Fano resonance in the whole spectral bands

Photonic temperature and wavelength metrology by spectral pattern recognition.

Spectral pattern recognition is used to measure temperature and generate calibrated wavelength/frequency combs using a single silicon waveguide ring resonator. The ring generates two incommensurate interleaving TE and TM spectral combs that shift independently with temperature to create a spectral pattern that is unique at every temperature. Following an initial calibration, the ring temperature can be determined by recognizing the spectral resonance pattern, and as a consequence, the wavelength of every resonance is also known. Two methods of pattern-based temperature retrieval are presented. In the first method, the ring is locked to a previously determined temperature set-point defined by the coincidence of only two specific TE and TM cavity modes. Based on a prior calibration at the set-point, the ring temperature and hence all resonance wavelengths are then known and the resulting comb can be used as a wavelength calibration reference. In this configuration, all reference comb wavelengths have been reproduced within a 5 pm accuracy across an 80 nm range by using an on-chip micro-heater to tune the ring. For more general photonic thermometry, a spectral correlation algorithm is developed to recognize a resonance pattern across a 30 nm wide spectral window and thereby determine ring temperature continuously to 50 mK accuracy. The correlation method is extended to simultaneously determine temperature and to identify and correct for wavelength calibration errors in the interrogating light source. The temperature and comb wavelength accuracy is limited primarily by the linewidth of the ring resonances, with accuracy and resolution scaling with the ring quality factor.

Multiphoton Interference in the Spectral Domain by Direct Heralding of Frequency Superposition States.

Multiphoton interference is central to photonic quantum information processing and quantum simulation, usually requiring multiple sources of nonclassical light followed by a unitary transformation on their modes. We observe interference in the four-photon events generated by a single silicon waveguide, where the different modes are six frequency channels. Rather than requiring a unitary transformation, the frequency correlations of the source are configured such that photons are generated in superposition states across multiple channels, and interference effects can be seen without further manipulation. The frequency correlations of the source also mean that it is effectively acting as multiple pair photon sources, generating photons in different spectral modes, which interfere with each other in a nontrivial manner. This suggests joint spectral engineering is a tool for controlling complex quantum photonic states without the difficulty of implementing spatially separate sources or a large unitary interferometer, which could have practical benefits in various applications of multiphoton interference.

Transfer-printed quantum-dot nanolasers on a silicon photonic circuit

Quantum-dot (QD) nanolasers integrated on a silicon photonic circuit are demonstrated for the first time. QD nanolasers based on one-dimensional photonic crystal nanocavities containing InAs/GaAs QDs are integrated on CMOS-processed silicon waveguides with silicon dioxide cladding. We employed transfer printing, whereby the three-dimensional stack of photonic nanostructures is assembled in a pick-and-place manner. The lasing operation and waveguide coupling of an assembled single nanolaser are confirmed through micro-photoluminescence spectroscopy. Furthermore, by repetitive transfer printing, two QD nanolasers integrated onto a single silicon waveguide are demonstrated, opening a path to the development of compact light sources potentially applicable to wavelength division multiplexing.

Dual-polarization wavelength conversion of 16-QAM signals in a single silicon waveguide with a lateral p-i-n diode [Invited

A polarization-diversity loop with a silicon waveguide with a lateral p-i-n diode as a nonlinear medium is used to realize polarization insensitive four-wave mixing. Wavelength conversion of seven dual-polarization 16-quadrature amplitude modulation (QAM) signals at 16 GBd is demonstrated with an optical signal-to-noise ratio penalty below 0.7 dB. High-quality converted signals are generated thanks to the low polarization dependence (≤0.5 dB) and the high conversion efficiency (CE) achievable. The strong Kerr nonlinearity in silicon and the decrease of detrimental free-carrier absorption due to the reverse-biased p-i-n diode are key in ensuring high CE levels.

Indium Tin Oxide Based Dual-Polarization Electro-Optic Intensity Modulator on a Single Silicon Waveguide

For high-speed optical transmission, polarization-division-multiplexing (PDM) is a promising technic to double the link capacity. However, most of on-chip PDM systems include a polarization beam splitter, a polarization rotator, and two modulators, which are costly and complex for integration. In this study, a novel dual-polarization electro-optic intensity modulator is proposed that is based on a single silicon waveguide with indium tin oxide (ITO) cladding. The design is validated by numerical simulation with commercial software Lumerical Solution. Based on the epsilon-near-zero effect of ITO, the device, on a single waveguide, manages to modulate simultaneously transverse electric (TE) and transverse magnetic (TM) modes with independent electrical driving signals. With a 75 μ m-long silicon rib waveguide, the extinction ratios (ERs) of both TE and TM modes can be around 15 dB, and the nonuniformity is around 0.5 dB. The 3 dB modulation bandwidths are 57.8 GHz and 65.9 GHz for TE and TM modulation, respectively. Within 1 dB ER nonuniformity, the device can operate at E -, S -, and C -band, which distinguishes itself by achieving wavelength-division-multiplexing compatible PDM and with only one single waveguide. To our best knowledge, the concept of independent and simultaneous dual-polarization modulation on a single waveguide is proposed for the first time. The modulator offers various merits including ultracompact size, high speed, and complementary metal oxide semiconductor (CMOS) compatibility.

On-chip optical interconnection by using integrated III-V laser diode and photodetector with silicon waveguide

On-chip integration of III-V laser diodes and photodetectors with silicon nanowire waveguides is demonstrated. Through flip-chip bonding of GaInNAs/GaAs laser diodes directly onto the silicon substrate, efficient heat dissipation was realized and characteristic temperatures as high as 132K were achieved. Spot-size converters for the laser-to-waveguide coupling were used, with efficiencies greater than 60%. The photodetectors were fabricated by bonding of InGaAs/InP wafers directly to silicon waveguides and formation of metal-semiconductor-metal structures, giving responsivities as high as 0.74 A/W. Both laser diode and the photodetector were integrated with a single silicon waveguide to demonstrate a complete on-chip optical transmission link.