Category Physics

Researchers have come up with a way to use one single device – such as a mobile phone or smartwatch – to wirelessly power up to 10 wearables on a user. This novel method uses the human body as a medium for transmitting power. Their system can also harvest unused energy from electronics in a typical home or office environment to power the wearables.

Advancements in wearable technology are reshaping the way we live, work and play, and also ho...

Acoustic waves in gases, liquids, and solids usually travel at an almost constant speed of sound. So-called rotons are an exception: their speed of sound changes significantly with the wavelength, and it is also possible that the waves travel backwards. Researchers at Karlsruhe Institute of Technology (KIT) are studying the possibilities of using rotons in artificial materials. These computer-designed metamaterials, produced by ultra-precise 3D laserprinting, might be used in the future to manipulate or direct sound in ways that have never been possible before. A report on the researchers’ work has been published in Nature Communications.

Rotons are quasiparticles, whic...

Prototype technology could enable smart home systems that don’t record speech. Microphones are perhaps the most common electronic sensor in the world, with an estimated 320 million listening for our commands in the world’s smart speakers. The trouble is that they’re capable of hearing everything else, too.

But now, a team of University of Michigan researchers has developed a system that can inform a smart home — or listen for the signal that would turn on a smart speaker — without eavesdropping on audible sound.

The key to the device, called PrivacyMic, is ultrasonic sound at frequencies above the range of human hearing...

A research team from the University of Massachusetts Amherst has created an electronic microsystem that can intelligently respond to information inputs without any external energy input, much like a self-autonomous living organism. The microsystem is constructed from a novel type of electronics that can process ultralow electronic signals and incorporates a device that can generate electricity “out of thin air” from the ambient environment.

The groundbreaking research was published June 7 in the journal Nature Communications.

Jun Yao, an assistant professor in the electrical and compu...