Two equations derived from first principles by Brian Josephson that characterize the device, somewhat like an I-V curve:where:
- : Josephson current
- : the Josephson phase, a function defined by the second equation plus initial conditions
- : input voltage of the system
- : current across the junction, determined by the input voltage
Note how these equations are not a typical I-V curve, as they are not an instantaneous dependency between voltage and current: the history of the voltage matters! Or in other words, the system has an internal state, represented by the Josephson phase at a given point in time.
To understand them better, it is important to look at some important cases separately:
- AC Josephson effect: V is a fixed DC voltage
A device that exhibits the Josephson effect.
TODO is there any relationship between this and the Josephson effect?
Experimental observation published as Experimental Evidence for Quantized Flux in Superconducting Cylinders.
This appears to happen to any superconducting loop, because the superconducting wave function has to be continuous.
Video "Superconducting Qubit by NTT SCL (2015)" suggests that anything in between gets cancelled out by a superposition of current in both directions.
- the basis for the most promising 2019 quantum computing implementation: superconducting quantum computer
- Josephson voltage standard: the most practical/precise Volt standard, which motivated the definition of the ampere in the 2019 redefinition of the SI base units
- SQUID devices, which are:
- very precise magnetometer
- the basis for superconducting quantum computers
Applications:
- because it has an even number of nucleons it is transparent to NMR, and therefore is useful in solvents for NMR spectroscopy
We can almost reach the Lie algebra of any isometry group in a single go. For every in the Lie algebra we must have:because has to be in the isometry group by definition as shown at Section "Lie algebra of a matrix Lie group".
Bibliography:
Islam has some really nice things in it.
Ciro Santilli especially appreciates the ideas of
Ciro Santilli appreciates this concept of "remembering the suffering of others" a lot due to Ciro Santilli's self perceived compassionate personality and Ciro Santilli's cheapness.
Bibliography:
- some good interview excerpts with some of the pioneers on Glory of the Geeks
There are unlisted articles, also show them or only show them.