Your Wi-Fi router emits terahertz waves, or electromagnetic waves, that have a frequency between what a microwave and an infrared light emit.
These waves, also known as T-rays, are almost everywhere in our day to day lives, and if harnessed correctly can serve as an energy source. This is what MIT researchers have been working on, and, in fact, have designed a blueprint for a device that could capture and convert these ambient terahertz waves into energy to charge up electronic devices.
Their findings were published in Science Advances.
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