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A full multicore fiber optic link is demonstrated, transmitting greater than 100 Gb/s through a single strand of multimode fiber for the first time. The fiber, which consists of seven graded-index multimode cores, is used to transmit up to 120 Gb/s over 100 m using a custom multicore-fiber interfacing transmitter and receiver. 2-D arrays of vertical-cavity surface-emitting lasers (VCSELs) and vertically illuminated photodiodes (PDs) are fabricated with a geometry corresponding to the outer six cores of the seven-core fiber, which is arranged in a hexagonal pattern. Both flip-chip and wire-bonding technologies are used to package the VCSEL and PD chips with multichannel transmitter and receiver integrated circuits. Amplitude and timing margins of the end-to-end signals are analyzed through bit-error-rate (BER) measurements. The effects of electrical and optical crosstalk are shown to result in negligible degradation to the BER performance. [ABSTRACT FROM PUBLISHER]

We report here on the design, fabrication, and characterization of highly integrated parallel optical transceivers designed for Tb/s-class module-to-module data transfer through polymer waveguides integrated into optical printed circuit boards (o-PCBs). The parallel optical transceiver is based on a through-silicon-via silicon carrier as the platform for integration of 24-channel vertical cavity surface-emitting laser and photodiode arrays with CMOS ICs. The Si carrier also includes optical vias (holes) for optical access to conventional surface-emitting 850 nm optoelectronic devices. The 48-channel 3-D transceiver optochips are flip-chip soldered to organic carriers to form transceiver optomodules. Fully functional optomodules with 24 transmitter + 24 receiver channels were assembled and characterized with transmitters operating up to 20 Gb/s/ch and receivers up to 15 Gb/s/ch. At 15 Gb/s, the 48-channel optomodules provide a bidirectional aggregate bandwidth of 360 Gb/s. In addition, o-PCBs have been developed using a 48-channel flex waveguide assembly attached to FR4 electronic boards. Incorporation of waveguide turning mirrors and lens arrays facilitates optical coupling to/from the o-PCB. Assembly of optomodules to the o-PCB using a ball grid array process provides both electrical and optical interconnections. An initial demonstration of the full module-to-module optical link achieved >; 20 bidirectional links at 10 Gb/s. At 15 Gb/s, operation at a bit error ratio of <; 10- 12 was demonstrated for 15 channels in each direction, realizing a record o-PCB link with a 225 Gb/s bidirectional aggregate data rate. [ABSTRACT FROM PUBLISHER]

The effect of applying feed-forward equalization (FFE) on the transmitter side is studied for three different full optical links. In contrast to all previous works, the FFE settings are optimized for a complete link, rather than just the vertical-cavity surface-emitting laser output. The approach results in dramatic improvements in total link performance: >; 6 dB in sensitivity, 3X in timing margin, and 2X in power efficiency at 15 Gb/s, and a record 5.7 pJ/bit at 20 Gb/s. [ABSTRACT FROM PUBLISHER]

We report an 850-nm, vertical-cavity surface-emitting laser (VCSEL)-based optical link that achieves new benchmarks in speed and power efficiency. The laser diode driver and receiver ICs are fabricated in standard 90-nm bulk CMOS, and the gallium arsenide optoelectronic devices are commercial components. An operation at a bit-error rate less than 10-12 at 25 Gb/s is achieved, representing the highest speed reported to date for a CMOS-based full optical link. At 22 Gb/s, the link power efficiency is 3.8 pJ/bit and improves further at lower data rates, attaining a minimum of 2.6 pJ/bit at 15 Gb/s. The efficiency numbers reported here, which include a complete accounting of the power dissipation of all the components, are the best reported for any optical interconnect in any technology. This work demonstrates the scalability of VCSEL-based links in both efficiency and speed to meet the demanding requirements of next-generation exa-scale computing and large data center systems. [ABSTRACT FROM PUBLISHER]