• Register
PhysicsOverflow is a next-generation academic platform for physicists and astronomers, including a community peer review system and a postgraduate-level discussion forum analogous to MathOverflow.

Welcome to PhysicsOverflow! PhysicsOverflow is an open platform for community peer review and graduate-level Physics discussion.

Please help promote PhysicsOverflow ads elsewhere if you like it.


New printer friendly PO pages!

Migration to Bielefeld University was successful!

Please vote for this year's PhysicsOverflow ads!

Please do help out in categorising submissions. Submit a paper to PhysicsOverflow!

... see more

Tools for paper authors

Submit paper
Claim Paper Authorship

Tools for SE users

Search User
Reclaim SE Account
Request Account Merger
Nativise imported posts
Claim post (deleted users)
Import SE post

Users whose questions have been imported from Physics Stack Exchange, Theoretical Physics Stack Exchange, or any other Stack Exchange site are kindly requested to reclaim their account and not to register as a new user.

Public \(\beta\) tools

Report a bug with a feature
Request a new functionality
404 page design
Send feedback


(propose a free ad)

Site Statistics

205 submissions , 163 unreviewed
5,037 questions , 2,191 unanswered
5,345 answers , 22,706 comments
1,470 users with positive rep
816 active unimported users
More ...

  Why is the total capacitance for the CPB-circuit a sum

+ 1 like - 0 dislike

In this document  (p.6 eqn. 2.1) and also in the general literature for the the basic Cooper pair box circuit the total capacitance \(C_\Sigma\) is the sum of the gate-capacitance \(C_g\) and the capacitance of the Josephson-Junction \(C_J\). Why is that the case? As far as I can see the elements are connected in series and thus only the inverses add up to the inverse of the total capacitance. What am I missing? Are  the capacitances actually connected in parallel? If so can somebody explain why they are considered in parallel, because I don't understand it.

Thanks in advance!

asked Jun 25, 2019 in Chat by anonymous [ no revision ]
recategorized Jun 28, 2019 by Dilaton

the junction is not a serial circuit. The 2 capacitors of the pass filters ( meaning 99.99% of the total junction capacitance ) are embeded in // circuits. Very interesting question when linked to a scale description... Perhaps to move to the chat forum?

Your answer

Please use answers only to (at least partly) answer questions. To comment, discuss, or ask for clarification, leave a comment instead.
To mask links under text, please type your text, highlight it, and click the "link" button. You can then enter your link URL.
Please consult the FAQ for as to how to format your post.
This is the answer box; if you want to write a comment instead, please use the 'add comment' button.
Live preview (may slow down editor)   Preview
Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
If you are a human please identify the position of the character covered by the symbol $\varnothing$ in the following word:
Then drag the red bullet below over the corresponding character of our banner. When you drop it there, the bullet changes to green (on slow internet connections after a few seconds).
Please complete the anti-spam verification

user contributions licensed under cc by-sa 3.0 with attribution required

Your rights