III/V-on-Si MQW lasers by using a novel photonic integration method of regrowth on a bonding template.

Silicon photonics is becoming a mainstream data-transmission solution for next-generation data centers, high-performance computers, and many emerging applications. The inefficiency of light emission in silicon still requires the integration of a III/V laser chip or optical gain materials onto a silicon substrate. A number of integration approaches, including flip-chip bonding, molecule or polymer wafer bonding, and monolithic III/V epitaxy, have been extensively explored in the past decade. Here, we demonstrate a novel photonic integration method of epitaxial regrowth of III/V on a III/V-on-SOI bonding template to realize heterogeneous lasers on silicon. This method decouples the correlated root causes, i.e., lattice, thermal, and domain mismatches, which are all responsible for a large number of detrimental dislocations in the heteroepitaxy process. The grown multi-quantum well vertical p-i-n diode laser structure shows a significantly low dislocation density of 9.5 × 104 cm-2, two orders of magnitude lower than the state-of-the-art conventional monolithic growth on Si. This low dislocation density would eliminate defect-induced laser lifetime concerns for practical applications. The fabricated lasers show room-temperature pulsed and continuous-wave lasing at 1.31 μm, with a minimal threshold current density of 813 A/cm2. This generic concept can be applied to other material systems to provide higher integration density, more functionalities and lower total cost for photonics as well as microelectronics, MEMS, and many other applications

Non-volatile heterogeneous III-V/Si photonics via optical charge-trap memory

We demonstrate, for the first time, non-volatile charge-trap flash memory (CTM) co-located with heterogeneous III-V/Si photonics. The wafer-bonded III-V/Si CTM cell facilitates non-volatile optical functionality for a variety of devices such as Mach-Zehnder Interferometers (MZIs), asymmetric MZI lattice filters, and ring resonator filters. The MZI CTM exhibits full write/erase operation (100 cycles with 500 states) with wavelength shifts of $\Delta\lambda_{non-volatile} = 1.16 nm$ ($\Delta n_{eff,non-volatile} ~ 2.5 \times 10^{-4}$) and a dynamic power consumption $<$ 20 pW (limited by measurement). Multi-bit write operation (2 bits) is also demonstrated and verified over a time duration of 24 hours and most likely beyond. The cascaded 2nd order ring resonator CTM filter exhibited an improved ER of ~ 7.11 dB compared to the MZI and wavelength shifts of $\Delta\lambda_{non-volatile} = 0.041 nm$ ($\Delta n_{eff, non-volatile} = 1.5 \times 10^{-4}$) with similar pW-level dynamic power consumption as the MZI CTM. The ability to co-locate photonic computing elements and non-volatile memory provides an attractive path towards eliminating the von-Neumann bottleneck

Low-loss hybrid silicon tapers

Two types of hybrid silicon tapers are studied. Single taper loss is 0.3 - 0.5 dB, enabling integration of III/V actives on silicon-on-insulator passive circuitry with low loss

Frequency comb dynamics of a 13 μm hybrid-silicon quantum dot semiconductor laser with optical injection

International audienceThis work reports on the influence of bias voltage applied on a saturable absorber (SA) on a subthreshold linewidth enhancement factor (LEF) in hybrid-silicon quantum dot optical frequency comb lasers. Results show that the reverse bias voltage on SA contributes to enlarge the LEF and improve the comb dynamics. Optical injection is also found to be able to improve the comb spectrum in terms of 3 dB bandwidth and its flatness. Such novel findings are promising for the development of high-speed dense wavelength-division multiplexing photonic integrated circuits in optical interconnects and datacom applications

III/V-on-Si MQW lasers by using a novel photonic integration method of regrowth on a bonding template.

Silicon photonics is becoming a mainstream data-transmission solution for next-generation data centers, high-performance computers, and many emerging applications. The inefficiency of light emission in silicon still requires the integration of a III/V laser chip or optical gain materials onto a silicon substrate. A number of integration approaches, including flip-chip bonding, molecule or polymer wafer bonding, and monolithic III/V epitaxy, have been extensively explored in the past decade. Here, we demonstrate a novel photonic integration method of epitaxial regrowth of III/V on a III/V-on-SOI bonding template to realize heterogeneous lasers on silicon. This method decouples the correlated root causes, i.e., lattice, thermal, and domain mismatches, which are all responsible for a large number of detrimental dislocations in the heteroepitaxy process. The grown multi-quantum well vertical p-i-n diode laser structure shows a significantly low dislocation density of 9.5 × 104 cm-2, two orders of magnitude lower than the state-of-the-art conventional monolithic growth on Si. This low dislocation density would eliminate defect-induced laser lifetime concerns for practical applications. The fabricated lasers show room-temperature pulsed and continuous-wave lasing at 1.31 μm, with a minimal threshold current density of 813 A/cm2. This generic concept can be applied to other material systems to provide higher integration density, more functionalities and lower total cost for photonics as well as microelectronics, MEMS, and many other applications

Integrated recirculating optical hybrid silicon buffers

We present our work on fully integrated hybrid silicon optical buffers capable of holding 40 byte packets at 40 Gb/s. These devices consist of low loss silicon waveguides and cascaded amplifiers to overcome passive losses in a 1.1 m long delay line. Since cascading multiple gain elements leads to ASE (noise) accumulation, reshaping elements in the form of saturable absorbers are integrated in the delay. Noise filtering in the buffer is investigated by simulating the eye diagram for a delay line with 1R regenerators and comparing it to that of a 2R regenerator. Finally, preliminary experimental data from the optical buffer is shown