What is the Josephson constant?
The Josephson constant is K_J = 4.835978484e14 Hz/V, exact by SI definition. It equals 2e/h.
Open the interactive PhysRef tool →Key facts
| Value | 4.835978484e14 Hz/V |
|---|---|
| Symbol | K_J |
| Relation | K_J = 2e/h |
| Exactness | Exact by SI definition (uncertainty 0) |
| Source | CODATA 2018 |
Frequently asked questions
What is the value of the Josephson constant?
K_J = 4.835978484e14 Hz/V, the proportionality between voltage and frequency in the Josephson effect.
What is the Josephson constant used for?
It underpins the modern volt standard via Josephson junctions, where V = f/K_J.
How is K_J defined?
K_J = 2e/h, the reciprocal of the magnetic flux quantum.
Related pages
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