CQED understanding superconducting qbits circuits

In summary: For more detailed information on circuit QED, I recommend that you read one of the many review articles (most of which are available on the arXiv) or contact university or company experts.
  • #1
maajdl
Gold Member
391
29
TL;DR Summary
modeling qbit circuit
I have read a little about cqed, "circuit quantum electrodynamics".
I would be interested in references to dig a qbit deeper in this topic!

I have seen lumped circuit diagrams for superconducting qbits.
The correspondance between classical and quantum models for these circuits is really interresting.
I have seen physical diagrams for how q-circuits are actually implemented.
The correspondance between these diagrams is not so obvious.

I would like to know more about how q-circuits are actually built
and how they could then be modeled or simulated or understood as lumped q-circuits.
I would especially like to understand in detail how the coupling works for setting the state or for reading the state.
For example, I have seen that micro transmission lines (resonators) are involved and I would like to know the principles of their physical modelling.
For example: do their shape matter or does only their length matter?

I guess it is essentially based on a classical model that is later quantified.
So in a sense, it is the classical models of these cicruits that matter first for my understanding.

Any references welcome!
 
Physics news on Phys.org
  • #2
I find a review in 2020 by web search
https://www.annualreviews.org/doi/10.1146/annurev-conmatphys-031119-050605
I hope you would find one of your taste in the web. If you need more detailed information I recommend you to go to referred papers or contact university or company experts. They would welcome ambitious young people to join the quantum engineering forces.
 
Last edited:
  • Informative
Likes maajdl
  • #3
The "original" circuit QED paper by Blais et al from 2004 is still a good reference.
There are lots of review articles (most available on the arXiv) including a recent one from some of the people who did the initial work
https://arxiv.org/abs/2005.12667

Another good resource is the Qiskit YouTube channel (Qiskit is IBM's quantum software framework) as well as the documentation for Qiskit Metal (which is a free design software for CQED circuits, although you also need a HFSS license to get the most out of it)

About your second question: CQED circuits are in terms of their EM behaviour really just "normal" microwave circuits albeit made using (mainly) superconducting conductors plus some non-linear elements (Josephson junctions).
Hence, the design flow is very similar to what one would typically use for any other MW circuit (say a telecom filter) : You usually would start by a lumped element version of the circuit you need and then you would start designing MW versions of each element: an LC resonator might be implemented as a quarter wavelength resonator, an inductor as a squiggly line etc
All of this design work is mainly done using conventional microwave software. Although increasingly some of the modelling and design is now done using specialised packages such as the aforementioned Qiskit Metal
 
Last edited:
  • Like
  • Informative
Likes maajdl and vanhees71

FAQ: CQED understanding superconducting qbits circuits

What is CQED and how does it relate to superconducting qubit circuits?

CQED stands for cavity quantum electrodynamics, which is a field of study that explores the interaction between light and matter at the quantum level. In the context of superconducting qubit circuits, CQED is used to manipulate and control the quantum states of the qubits using photons in a cavity. This allows for faster and more precise operations on the qubits.

How do superconducting qubit circuits work?

Superconducting qubit circuits use superconducting materials to create qubits, which are the basic units of quantum information. These qubits are then connected to other components, such as resonators and control lines, to form a circuit. By manipulating the qubits using microwave pulses and controlling their interactions with the other components, quantum operations can be performed on the qubits.

What are the advantages of using superconducting qubit circuits?

Superconducting qubit circuits have several advantages over other types of quantum computing systems. They are relatively easy to fabricate and operate, can be scaled up to larger systems, and have long coherence times, meaning that the quantum states of the qubits can be maintained for longer periods of time. They also have a high degree of control and can perform operations quickly and accurately.

What are the challenges of understanding superconducting qubit circuits?

One of the main challenges in understanding superconducting qubit circuits is the complex nature of their behavior. The interactions between the qubits and other components can be difficult to model and predict, and there are many factors that can affect the performance of the qubits. Additionally, the quantum behavior of the system can be sensitive to external disturbances, making it challenging to maintain the delicate quantum states of the qubits.

How are superconducting qubit circuits being used in quantum computing?

Superconducting qubit circuits are a leading platform for quantum computing research and development. They are being used to explore quantum algorithms, error correction techniques, and new methods for controlling and manipulating quantum states. They are also being integrated into larger quantum computing systems and are expected to play a key role in the development of practical quantum computers in the future.

Similar threads

Replies
2
Views
812
Replies
6
Views
2K
Replies
3
Views
1K
Replies
1
Views
899
Replies
1
Views
2K
Replies
5
Views
2K
Back
Top