We review recent breakthroughs in the silicon photonic technology and components, and describe progress in silicon photonic integrated circuits. Heterogeneous silicon photonics has recently demonstrated performance that significantly outperforms native III/V components. The impact active silicon photonic integrated circuits could have on interconnects, telecommunications, sensors, and silicon electronics is reviewed.

Heterogeneous Silicon Photonic Integrated Circuits

Silicon photonics enables wafer-scale integration of optical functionalities on chip. Silicon-based laser frequency combs can provide integrated sources of mutually coherent laser lines for terabit-per-second transceivers, parallel coherent light detection and ranging, or photonics-assisted signal processing. We report heterogeneously integrated laser soliton microcombs combining both indium phospide/silicon (InP/Si) semiconductor lasers and ultralow-loss silicon nitride (Si3N4) microresonators on a monolithic silicon substrate. Thousands of devices can be produced from a single wafer by using complementary metal-oxide-semiconductor-compatible techniques. With on-chip electrical control of the laser-microresonator relative optical phase, these devices can output single-soliton microcombs with a 100-gigahertz repetition rate. Furthermore, we observe laser frequency noise reduction due to self-injection locking of the InP/Si laser to the Si3N4 microresonator. Our approach provides a route for large-volume, low-cost manufacturing of narrow-linewidth, chip-based frequency combs for next-generation high-capacity transceivers, data centers, space and mobile platforms.

Laser soliton microcombs heterogeneously integrated on silicon

http://www.sciencemadness.org/talk/files.php?pid=173612&aid=10122

Frequency noise characterisation of narrow linewidth diode lasers

Two different laser phase noise measurement techniques are compared. One of these two techniques is based on a conventional and low-cost delay line system, which is usually set up for the linewidth measurement of semiconductor lasers. The results obtained with both techniques on a high-spectral-purity laser agree well and confirm the interest of the low-cost technique. Moreover, an extraction of the laser linewidth using computer-aided design tools is performed.

https://hal.archives-ouvertes.fr/hal-00609221/document

Phase noise measurement of a narrow linewidth CW laser using delay line approaches

An asymmetrical π-phase-shift distributed feedback (DFB) fiber laser written in erbium/ytterbium co-doped fiber is fabricated. A new self-injection locking method is employed to make the proposed DFB fiber laser operate in single polarization states, which is composed of a polarization-dependent isolator and an optical circulator. The output character is investigated. 9.5 mW of the backward output power is obtained at the 159 mW pump power. The output power in one side is much higher than that in the other side, indicating that the DFB fiber laser operates in the unidirectional output. The delayed self-homodyne measurement is employed to detect the radio frequency spectrum of the DFB fiber laser. This novel single polarization DFB fiber laser has the potential application in the fiber optical sensor and optical communications.

Mika Tossavainen

Papers

Laser linewidth measurements using self-homodyne detection with short delay