Hybrid single quantum well InP/Si nanobeam lasers for silicon photonics

Abstract

We report on a hybrid InP/Si photonic crystal nanobeam laser emitting at 1578 nm with a low threshold power of ∼14.7 μW. Laser gain is provided from a single InAsP quantum well embedded in a 155 nm InP layer bonded on a standard silicon-on-insulator wafer. This miniaturized nanolaser, with an extremely small modal volume of 0.375λ∕n 3 , is a promising and efficient light source for silicon photonics. However, the capability of generating light on silicon has been one of the daunting problems to overcome owing to its indirect electronic bandgap [9]. Faced with this long-standing issue, several research groups have proposed heterogeneous integration of III-V quantum well (QW) materials on top of silicon structures to generate light at the telecommunication wavelengths [9][10][11][12][13][14][15].In this Letter, we demonstrate a novel low threshold and optically pumped single QW nanobeam laser, defined by means of a heterogeneous integration of an InP layer (with a single InAs 0.65 P 0.35 QW embedded) on silicon-on-insulator.First, we focused on the design of the heterogeneous InP/Si nanobeam cavity and pursued a high Q-factor in an attempt to reduce the lasing threshold. Simulations were made using finite-difference time-domain (FDTD) models, where the well-known techniques to design 1D photonics crystal nanobeam cavities with the desired figures of merits were employed [16][17][18][19].Preliminarily simulations showed that a hybrid bilayer of 155 nm thick InP on top of 220 nm thick silicon-oninsulator, 500 nm wide, and holes suitably designed can form a heterogeneous nanobeam cavity with a theoretical Q-factor as high as 2.27 × 10 6 and modal volume as low as 0.375λ∕n 3 . To attain such figures of merit, the reflector sections of the cavity are designed with a periodic structure of 13 holes, drilled through both layers of InP and Si, with periodicity α 370 nm. In addition, a linear tapered section (from 0.28α to 0.22α) is suitably designed with five holes, drilled through both layers, to precisely phase match the waveguide and Bloch modes [17]. Finally, the Q-factor and resonant wavelength are tailored by varying the length of the dielectric section on the center of the nanobeam cavity [S in Fig. 1(b)].Figure 1(a) shows the theoretical Q-factor and resonant wavelength of the heterogeneous Si/InP nanobeam

Monolithic InGaAs Nanowire Array Lasers on Silicon-on-Insulator Operating at Room Temperature

“…We adopt a one-dimensional (1D) photonic crystal cavity, which can achieve a high quality ( Q ) factor comparable with the two-dimensional (2D) counterpart, , while requiring a much smaller footprint and number of nanowires. The schematic illustration of our nanowire array laser is shown in Figure a.…”

“…Advancing from the lasing demonstration of nanowire array cavities formed on planar SOI substrates, we also demonstrate SOI waveguide-coupled nanowire array lasers integrated on silicon mesas, which supports the compatibility of the proposed lasers with PICs. We adopt a one-dimensional (1D) photonic crystal cavity, which can achieve a high quality (Q) factor comparable with the two-dimensional (2D) counterpart, 19,20 while requiring a much smaller footprint and number of nanowires. The schematic illustration of our nanowire array laser is shown in Figure 1a.…”

A printed nanobeam laser on a SiO_2/Si substrate for low-threshold continuous-wave operation

“…Indeed, there have recently been several efforts to integrate III-V quantum well (QW) PC lasers on Si-chips [12][13][14][15][16][17][18]; various wafer bonding techniques such as molecular bonding [12,14,18], adhesive bonding [15][16][17], and metallic dry bonding [13] have been proposed and employed to bond the III-V QW material onto Si substrate prior to the fabrication of PC laser structures. Among these techniques, the adhesive bonding method is most widely used due to the fact that it does not have stringent interface requirements in contrast to the other bonding processes.…”

Experimental demonstration of a reconfigurable silicon thermo-optical device based on spectral tuning of ring resonators for optical signal processing

“…For the past decade, several research groups have demonstrated essential building blocks to process optical signals, for example: efficient and broadband input/output coupling systems from optical fibers to optical waveguides [3], high-speed electro-optic modulators [4][5][6], chip-scale ultrafast pulse compressor [7], tunable filters [8,9], polarization-independent devices [10], heterogeneous integration on silicon-on-insulator (SOI) to produce light sources and photodetectors [11][12][13][14][15][16][17][18][19], as well as unidirectional [20] and nonreciprocal devices [21,22], amongst others.…”