Not exactly "nanotech", more micro-sensor tech, is this research:https://www.nature.c...1378-020-0173-z
Magnetic sensing is present in our everyday interactions with consumer electronics and demonstrates the potential for the measurement of extremely weak biomagnetic fields, such as those of the heart and brain. In this work, we leverage the many benefits of microelectromechanical system (MEMS) devices to fabricate a small, low-power, and inexpensive sensor whose resolution is in the range of biomagnetic fields. At present, biomagnetic fields are measured only by expensive mechanisms such as optical pumping and superconducting quantum interference devices (SQUIDs), suggesting a large opportunity for MEMS technology in this work. The prototype fabrication is achieved by assembling micro-objects, including a permanent micromagnet, onto a postrelease commercial MEMS accelerometer using a pick-and-place technique. With this system, we demonstrate a room-temperature MEMS magnetic gradiometer. In air, the sensor’s response is linear, with a resolution of 1.1 nT cm−1, spans over 3 decades of dynamic range to 4.6 µT cm−1, and is capable of off-resonance measurements at low frequencies. In a 1 mTorr vacuum with 20 dB magnetic shielding, the sensor achieves a 100 pT cm−1 resolution at resonance. This resolution represents a 30-fold improvement compared with that of MEMS magnetometer technology and a 1000-fold improvement compared with that of MEMS gradiometer technology. The sensor is capable of a small spatial resolution with a magnetic sensing element of 0.25 mm along its sensitive axis, a >4-fold improvement compared with that of MEMS gradiometer technology. The calculated noise floor of this platform is 110 fT cm−1 Hz−1/2, and thus, these devices hold promise for both magnetocardiography (MCG) and magnetoencephalography (MEG) applications.
That sounds amazing! It sounds like they have achieved using a cheap MEMS device what previously took SQUIDS (=Superconducting Quantum Interference Devices) or OPMs (=Optically-pumped magnetometers), both of which are expensive and usually involve exotic materials (like rubidium vapor sensors).
In fact, it sounds insane! This means we could see cheap, wearable brain scanners and body scanners (e.g. heart monitors), that read the body's faint biomagnetic signals. It's like something off of Star Trek.
I think a sensor technology that would be truly
disruptive is a cheap, tiny (chip-sized), room temperature and higher, robust-to-noise, durable (long-lasting), super-accurate full tensor gravity gradiometer. I can think of lots and lots of uses of such a thing; but it would probably be outlawed, due to security concerns -- maybe it can be kept hidden inside of products, like the dangerous materials inside some fire alarms.
One use of such a thing is that it would allow driverless cars to tell whether an object in front of them is light and harmless (like a plastic bag) or a big, heavy hunk of metal that looks
like a plastic bag, but isn't. The same for home robots. They would know not to run into something, as it's bulky and heavy.