Thermostable microring modulators for use in optical devices

Unmet Need: Thermostable modulators for silicon photonic products

With the growing need for bandwidth, there has been a push for optical communication at distances and scales smaller than originally anticipated, leading to developments of optical links in technologies as small as a microchip. The silicon photonics platform, with its ability to manifest CMOS-compatible photonic devices, is promising for use in next-generation optical links. In particular, microring-based silicon photonic devices have been shown to push the boundaries on the aforementioned metrics of size and energy efficiency. However, currently available microring modulators are extremely susceptible to fluctuations in temperature or to drifts in the laser wavelength, stymying their usefulness in these types of products.

The Technology: Thermostable microring resonator for error-free performance in optical devices

This technology stabilizes silicon microring modulators by taking advantage of the mean-power monitoring method. An integrated photodetector measures the power of the microring modulator, providing local measurements of the average power. If the modulator should drift due to fluctuations in the temperature, the mean optical power will also change. This is used as a feedback measure to actively control an integrated heater, counteracting the local temperature of the microring modulator. This stabilizes the resonant wavelength of the microring modulator to maintain error-free performance in the presence of thermal fluctuations. Furthermore, because all these components are interfaced with low-speed and small-footprint electronic circuitry, this relatively simple technology can easily be integrated on a microchip and remain energy efficient.

This technology has been validated using a silicon microring modulator.

Applications:

Microring modulators in silicon photonics for optical microchip development
Optical transmitters
Optical gyroscopes
Creating other thermostable optical or electro-optic modulators

Advantages:

Thermostable
Reduced size
Consumes much less power than traditional modulators
Simple electronic implementation
High data bit rates

Lead Inventor:

Keren Bergman, Ph.D.

Patent Information:

Patent Issued

Related Publications:

Padmaraju K, Logan DF, Zhu X, Ackert JJ, Knights AP, Bergman K. “Integrated thermal stabilization of a microring modulator” Opt Express. 2013 Jun 10; 21(12): 14342-14350.

Tech Ventures Reference:

IR CU14094
Licensing Contact: Greg Maskel