Widely tunable 23  μm III-V-on-silicon Vernier lasers for broadband spectroscopic sensing

Abstract

Heterogeneously integrating III-V materials on silicon photonic integrated circuits has emerged as a promising approach to make advanced laser sources for optical communication and sensing applications. Tunable semiconductor lasers operating in the 2-2.5 µm are of great interest for industrial and medical applications since many gases (e.g., CO2, CO, CH4) and bio-molecules (such as blood glucose) have strong absorption features in this wavelength region. The development of integrated tunable laser sources in this wavelength range enables low-cost and miniature spectroscopic sensors. Here we report heterogeneously integrated widely tunable III-V-on-silicon Vernier lasers using two silicon micro-ring resonators as the wavelength tuning components. The laser has a wavelength tuning range of more than 40 nm near 2.35 µm. By combing two lasers with different distributed Bragg reflectors, a tuning range of more than 70 nm is achieved. Over the whole tuning range, the side mode suppression ratio (SMSR) is higher than 35 dB. As a proof-of-principle, this III-Von-silicon Vernier laser is used to measure the absorption lines of CO. The measurement results match very well with the HITRAN database and indicate that this laser is suitable for broadband spectroscopy.

Mid-infrared laser diodes epitaxially grown on on-axis (001) silicon

“…The point that remains to be unlocked in order to achieve compact mid-IR sensors is the large-scale, cost-effective integration of III-V semiconductor lasers. Although most integration schemes until now have relied on heterogeneous bonding [10][11][12][13], there is increasing evidence that the direct epitaxial growth of the III-V semiconductor laser heterostructure on Si should outperform them, provided on-axis, CMOS-compatible (001)-oriented Si substrates can be used [14]. This last integration strategy, however, is challenged by the conjunction of large thermal, lattice, and polarity mismatches between the Si substrate and III-V materials [15].…”

Widely Tunable III–V/Silicon Lasers for Spectroscopy in the Short-Wave Infrared

“…In the last section, we showed that integrating a series of DFB lasers with silicon photonics beam combiners enables widely tunable single-mode laser sources with mode hop free tuning. In this section, we summarize our recent results on another solution to realize widely tunable laser sources for spectroscopy: heterogeneously integrating short-wave infrared III-V SOAs with widely tunable silicon photonic filters [37]. The schematic of a widely tunable III-V-on-silicon laser using a silicon photonics Vernier filter to select the lasing wavelength is shown in Fig.…”

Design and Simulation Investigation of Si3N4 Photonics Circuits for Wideband On-Chip Optical Gas Sensing around 2 µm Optical Wavelength

“…For the ~2 μm wavelength range, besides its potential for optical communication [ 23 , 24 ], several important gases also have sufficiently strong absorption bands in such wavelength ranges with sensing applications in environmental and process controls such as H 2 O, NH 3 , and CO 2 [ 25 ]. In comparison with the longer wavelength regions, photonic components in the short-wave infrared could be advantageous for the development of low-cost sensors and detectors without cooling [ 26 , 27 , 28 ]. Recent research investigation has included on-chip room-temperature optical sources and optical detection around ~2 μm wavelength ranges based on heterogeneous integration of III-V semiconductors on silicon such as GeSn [ 29 , 30 , 31 ], InP [ 32 ], strained InGaAs [ 33 , 34 ], or GaSb [ 23 , 27 ].…”