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Challenges of Energy Harvesting

PHYSICS BEHIND RFID SMART CARD SECURITY IN CONTEXT OF PRIVACY MSc Thesis

radiated power in the form of air-pressure variations of 10^(-6) watts at 400 cps
Communication by Means of Reflected Power

decisive niches for low-energy harvesters??

Radio-Frequency Rectifier for Electromagnetic Energy Harvesting: Development Path and Future Outlook

The MTJ technology using MgO barrier is only ten years
old, but it is already manufactured for massive MRAM
applications. Although the fabrication process of spindiode
is very complex, spindiode can benefit from a large market
of MRAM that could guarantee an easy fabrication,
eventually at a lower cost. From the understanding of
rectification mechanisms, MTJ is clearly favored by the
spin-dependent transport, and even if actual responsivity is
very low because of a weak nonlinearity with the current
spindiode samples available to us, a high responsivity is
expected if the spindiode can be engineered to meet the
requirements of nonlinearity. In some cases, the spintorque diode effect could also provide a step further to
reach higher performances. As for parasitic limitations,
research efforts on interfacial resistance are expected to
play a positive role in improving the frequency behavior.

What If Your Fitbit Could Run on a Wi-Fi Signal?

MIT-based research

Batteryless energy harvester
Running electronics on body heat