Silicon photonics combined with complementary metal–oxide–semiconductor (CMOS) electronics leveraging wavelength-division multiplexing (WDM) are of interest for AI, optical computing, and high-speed Optical IO applications [1,2]. To power these applications, multi-wavelength light sources based on laser arrays [3] or mode locked lasers (MLL) have been proposed and demonstrated [4]. As optical sources mature, the CW-WDM multisource agreement (MSA) has emerged to define a set of wavelength grids and power levels so different applications can leverage a common set of laser technologies [5]. In this paper we demonstrate the first multi-wavelength optical source compliant with the CW-WDM MSA standard that operates from room temperatures through 100°C. The SuperNovaTM outputs 8 wavelengths across 8 fibers for a total of 64 optical carriers and complies with the 8+1 MSA wavelength plan (1 optional wavelength) with channels spaced at 400+/-100 GHz and output power within the Type 2 power class. The optical source is mode hop free with >40dB SMSR, <145 dB/Hz RIN, and <20 MHz linewidth across all channels and all operating conditions.

We demonstrate a CW-WDM MSA compliant multi-wavelength source driving an error-free WDM CMOS optical link. The SuperNova™ operates up to 100°C and outputs 64 optical carriers (8 wavelengths x 8 fibers), and together with the TeraPHY™ chiplet, drives up to 2 Tbps from a CMOS die.

Heterogenous co-packaging of optical I/O with compute, memory or switch nodes will deliver significant improvements in power, bandwidth and reach in data center and high-performance computing applications. A first-ever real-ized and validated 5.12 Tbps co-packaged FPGA with optical I/O is presented. The Multi-Chip Package integrates a 14nm FPGA die with five Ayar Labs TeraPHY™ optical I/O chiplets.

We demonstrate 128 Gbps/port (8-λ×16 Gbps/λ) natively error-free transmission across eight optical ports using a 8-port, 8-λ/port WDM remote laser source and a pair of monolithically integrated CMOS optical I/O chiplets with 4.96-5.56 pJ/bit optical Tx+Rx chiplet energy efficiency.

We demonstrate an electro-optic platform enabling a direct optical I/O interface in an ASIC package. The $5.5\mathrm{x}8.9\mathrm{mm}^{2}$ chiplet uses the Advanced Interface Bus (AIB), a parallel digital interface, to communicate to a host ASIC and integrates high-speed digital/analog circuits, optical modulators, photodetectors, and waveguides. Transmitters and receivers demonstrate data-rates up to 25Gbps at 4.9pJ/bit (Tx+Rx) and <10−12 BER error-free operation. We show a 32-channel, 512Gbps aggregate (across 4 Tx ports) wavelength-division multiplexed (WDM) transmit demonstration from a TeraPHY chiplet, running at 16Gbps per wavelength and 8 simultaneous wavelengths per port.

In this article, we present TeraPHY, a monolithic electronic-photonic chiplet technology for low power and low latency, multi-Tb/s chip-to-chip communications. Integration of the TeraPHY optical technology with open source advanced interconnect bus interface enables communication between chips at board, rack, and row level at the energy and latency cost of in-package interconnect. This enables the design of logically connected but physically separated large-scale and high-performance digital systems. The copackaging integration approach is demonstrated by integrating the TeraPHY die into the Intel Stratix10 FPGA multichip package.

Light absorption at the facet of a high power diode laser can lead to severe heating and catastrophic optical damage. In this work, a combination of high resolution thermoreflectance imaging and a detailed heat transport model of the diode chip are used to measure facet absorption in diode lasers. This approach permits a direct measurement of the effectiveness of passivation layers in improving facet robustness and device lifetime. The ability to quantify facet absorption is an essential step toward enabling rapid development of alternative passivation technologies and improving the reliability and maximum output power of diode laser systems.

Severe heating due to partial absorption of outcoupled emission at the facet of a high-power diode laser can lead to catastrophic optical damage. The degree of absorption and subsequent heating at the facet is a function of the emission wavelength, the absorption properties of facet coatings and passivation layers, and the age of the device. The ability to quantify facet absorption is an essential step toward improving the reliability of diode laser systems and rapid development of passivation technologies. In this work, we have developed a technique to measure facet absorption in diode lasers using a combination of facet thermoreflectance imaging and a heat transport model. The approach can be used for a wide range of both coated and uncoated diode lasers.

Thermoreflectance imaging enables noncontact mapping of surface temperature with high spatial resolution and high temperature resolution in electronic and optoelectronic devices. Recently we have applied charge-coupled device (CCD) based thermoreflectance imaging to study facet heating in high-power diode lasers. Sources of facet heating we have examined include back-irradiance as well as optical absorption of laser light at the outcoupling facet prior to emission. For the latter we have combined temperature measurements with a thermal model to derive facet optical absorption and have studied its evolution as the device ages.

Severe heating due to partial absorption of outcoupled emission at the facet of a high-power diode laser can lead to catastrophic optical damage. The degree of absorption and subsequent heating at the facet is a function of the emission wavelength, the absorption properties of facet coatings and passivation layers, and the age of the device. The ability to quantify facet absorption is an essential step toward improving the reliability and maximum output power of diode laser systems. In this work, we have developed a technique to measure facet absorption in diode lasers using a combination of facet thermoreflectance imaging and a heat transport model. The approach can be used for a wide range of both coated and uncoated diode lasers.

In optical systems employing high-power diode lasers, back-irradiance of emission onto the laser facet has been found to contribute to catastrophic optical damage. In this paper, thermoreflectance imaging has been used to measure quantum well temperature rise at the facet for diode lasers emitting at several wavelengths under a wide range of back-irradiance beam positions. For TM-polarized diode lasers operating near 800 nm, the quantum well temperature at the facet is found to reach a maximum when back-irradiance is positioned at the cladding-substrate interface. For TE-polarized lasers operating near 900 nm, a similar effect is observed, albeit with lower magnitude. Interestingly, a second maximum of similar magnitude is observed when back-irradiance is centered on the metal-semiconductor ohmic contact interface. For TE-polarized lasers operating near 1000 nm, the cladding-substrate critical point disappears and the critical point at the metal-semiconductor interface intensifies. The dependence of the critical back-irradiance spot location on operating wavelength originates in the spectral absorptivities of the device's constituent materials. In addition, the incident light's polarization can affect its absorption in the metallic solder. These measurements provide key insights into the potential thermal contribution of back-irradiance to catastrophic optical damage in diode lasers at various operating wavelengths.

Catastrophic failure of diode pumps in laser systems exhibiting hack-irradiance is a common occurrence yet poorly understood. Prior paper has established boundaries for time-zero failures, but these results cannot he used to deduce safe back-irradiance levels for long-term reliable operation. In this paper, a framework to describe the impact of back-irradiance on the reliability of diode pumps is established. The root-cause of back-irradiance induced failure is identified as thermal in nature. The approach follows conventional reliability methodologies by treating the parameters of back-irradiance as stressors, which accelerate failures.

The two-dimensional (2D) temperature profile of a high-power junction-down broad-area diode laser facet subject to back-irradiance (BI) is studied via CCD-based thermoreflectance (TR) imaging and finite element modeling. The temperature rise in the active region (ΔΤAR) is determined at different diode laser optical powers, back-irradiance reflectance levels, and back-irradiance spot locations. Interestingly, our study shows that ΔΤAR rises sharpest not when the back-irradiance is boresight-aligned with the active region but rather when it is centered in the absorbing substrate approximately 5 μm away from the active region, a distance roughly equal to half of the back-irradiance spot FWHM (9 μm). At this critical location, ΔΤAR is found to increase by nearly a factor of three compared to its increase without back-irradiance. This provides insight on an important location for back-irradiance that may be correlated with catastrophic optical damage (COD) for diode lasers fabricated on absorbing substrates, and also suggests a thermal basis for truncated lifetime and deegraded performance for diode lasers experiencing backirradiance.

Back-irradiance testing of high power diode lasers with absorbing substrates reveals catastrophic failure occurs when the return spot is shifted slightly with respect to the quantum well (into the substrate). Thermoreflectance temperature mapping shows this position to be the point of maximum facet temperature rise at the active region. Finite element thermal modelling, which is in close agreement with thermoreflectance results, indicates a root cause of thermal cross-heating between the absorbed back-irradiance light in the substrate and heating in the active region.

High thermal conductivity in amorphous polymer films via ionization-induced chain extension and stiffening, and dense packing.