Can be used as a very precise magnetometer.
There are high temperature yttrium barium copper oxide ones that work on liquid nitrogen.
Video 1. Superconducting Quantum Interference Device by Felipe Contipelli (2019) Source. Good intuiotionistic video. Some points deserved a bit more detail.
Video 2. Mishmash of SQUID interviews and talks by Bartek Glowaki. Source.
The videos come from: Vintage.
Mentions that the SQUID device is analogous to a double-slit experiment.
One of the segments is by John Clarke.
Video 3. Superconducting Quantum Interference Devices by UNSW Physics (2020) Source.
An experimental lab video for COVID-19 lockdown. Thanks, COVID-19. Presented by a cute and awkward Adam Stewart.
Uses a SQUID device and control system made by STAR Cryoelectronics. We can see Mr. SQUID EB-03 written on the probe and control box, that is their educational product.
As mentioned on the Mr. SQUID specs, it is a high-temperature superconductor, so liquid nitrogen is used.
He then measures the I-V curve on an Agilent Technologies oscilloscope.
Unfortunately, the video doesn't explain very well what is happening behind the scenes, e.g. with a circuit diagram. That is the curse of university laboratory videos: some of them assume that students will have material from other internal sources.
Video 4. The Ubiquitous SQUID by John Clarke (2018) Source.
In Ciro's ASCII art circuit diagram notation:
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