1
$\begingroup$

I've been trying to wrap my head around quantum computing, with mixed success. I have a reasonable understanding of how quantum circuits work and the basic principles. However, there is one big missing piece in my understanding, which I've not been able to fill be googling ...

You can use a tool like qiskit to create a quantum circuit, then send it to a cloud quantum computer. How does this circuit get constructed?

With a digital computer, it would either have to be assembled manually, or simulated. Neither seem practical.

Are quantum circuits assembled by tiny robots? (please say they are!)

$\endgroup$
2
  • 1
    $\begingroup$ Quantum circuits are abstract representations of quantum computations. When you submit a quantum circuit, it is queued, then compiled to a match the hardware device and finally executed. No tiny robots are involved, sorry. $\endgroup$ Commented Feb 27, 2023 at 11:08
  • 1
    $\begingroup$ it's a bit like saying that when you write code and have it executed on your pc there's tiny robots "assembling the classical circuit". The "circuit" is just a way to represent a sequence of operations that will be implemented on some physical substrate. From this perspective, the same thing happens for the quantum case. Except of course the types of operations and physical systems involved are quite different. $\endgroup$
    – glS
    Commented Feb 27, 2023 at 20:52

1 Answer 1

1
$\begingroup$

I think the notion of "quantum circuit" is a bit confusing: it tricks us by making us think during the compilation an electrical signal is going a physical circuit made of wires and logical gates, a bit like in classical computing. Actually, in quantum computing the circuit refers to a timeline not a physical circuit: when you build your circuit (on qiskit for example) you rather build a set of instruction sent to the qubits than a physical circuit. In fact, you can see the quantum chip as a grid of qubits and the quantum circuit as a set instructions to lead the interaction between those qubits. For example, in the case of superconducting qubits, a quantum gate corresponds to an electromagnetic pulse sent the qubits, therefore your quantum circuit is a set of electomagnetic pulses with a well chosen frequency/duration corresponding to the gates of your circuit, and no need to build a new chip :)

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.