Kotura Announces Technology Breakthrough in Low Voltage, High Speed Silicon Photonic Modulator

Kotura, Inc., a leading provider of Silicon Photonics products, today announced demonstration of an industry leading modulator with two-volt, peak-to-peak driving voltage, and permitting the use of inexpensive CMOS drivers. Equally impressive, the Kotura modulator achieved speeds in excess of 11 GHz and an ultra-low energy consumption of 50 femtoJoules per bit. The on chip device loss of 2 dB is among the lowest ever demonstrated.

“This technology breakthrough will enable the development of silicon photonics circuits for optical interconnect,” commented Dr. Ashok Krishnamoorthy, Principal Investigator on this project and a Distinguished engineer and Director at Sun Microsystems. “This promises to significantly increase the penetration of optical interconnects within computing systems – starting with the high-end, where interconnect is a bottleneck, and working down into volume applications. This development opens the door for wavelength-multiplexed optical interconnects, which will reduce the complexity impact of connectors and cabling in such systems. Silicon photonics solves this problem by enabling high bandwidth connectivity over longer distances at lower power than copper wires. A high-speed, low-power modulator is a key component in these circuits.”

“WDM has the potential to lower the cabling complexity and cost of optical interconnects by orders of magnitude” added Mehdi Asghari, CTO of Kotura. “A single silicon photonics device will require 10’s to 100’s of modulators, one for each wavelength of light. Our modulator has the right combination of low drive voltage, low power consumption, small size and low insertion loss to integrate many of these into a single chip.”

The Kotura modulator was developed as part of the DAPRA’s Ultraperformance Nanophotonic Intrachip Communications (UNIC) program in conjunction with Sun Microsystems, under the leadership of Dr. Jagdeep Shah. A technical paper, “Low Vpp, ultralow-energy, compact, high-speed silicon electro-optic modulator,” by Dong et al. was recently published in Optics Express, The International Electronic Journal of Optics.

The power levels per bit are what are needed to achieve 80 terabit per second. More must be done to get the communication speed up.