New Native Gates page

[abbycross]

Closes #113

Kevin noted that the native gates appear to be the same for all members of each processor family. I've added the gates associated with each family to the Processor types page as well.

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[abbycross]

Some thoughts (from @beckykd ):

• update language "Now..."

• how do you know which backends support condiditonal reset? Clarify in the beginning that not all support it and tell them how to figure it out. **note: this IS explained later. Move up that instruction to before you specify your backend. This just checks a specific backend though. How to find one except by trial and error? maybe it's supported on all backends now?

• ibmq_paris has been retired. Should this run on a fake backend? But fake backends don't seem to have configuration objects.

• On the code IBMQ.load_account(): DeprecationWarning: The qiskit.IBMQ entrypoint and the qiskit-ibmq-provider package (accessible from 'qiskit.providers.ibmq`) are deprecated and will be removed in a future release. (need job monitor from elsewhere?)

This code works, but I didn’t go much further because I’m afraid to run things on real systems:

service = QiskitRuntimeService(channel="ibm_quantum")

backend = service.get_backend("ibm_brisbane")

config = backend.configuration()

config.supported_instructions

• Do we still need "Note: These features require qiskit > 0.22.0 as they rely on qiskit-terra > 0.16.0." ? Is anyone using something that old?

• Verify "Note that reset is currently only enabled for quantum circuits (not pulse schedules)."

[Eric-Arellano]

Do we still need "Note: These features require qiskit > 0.22.0 as they rely on qiskit-terra > 0.16.0." ? Is anyone using something that old?

Definitely not. I'd assume our docs are for Qiskit 0.43 and newer, or maybe even 0.44 and newer. Once 1.0 is released, the plan is to focus on Qiskit 1.0.

[abbycross]

Clarification from Blake: I think all we need is a concise summary of the native gateset supported by our various hardware platforms. RESET needs a little additional explanation to communicate that RESET is not the same as the initialization done at the start of your circuit to prepare the all 0's state.
Also, init_qubits flag if it is an option supported by Sampler

[beckykd]

init_qubits flag if it is an option supported by Sampler

Confirmed that Sampler and Estimator support init_qubits.

[kevinsung]

Suggested change

By default, the `init_qubits` flag is set to True. If the `init_qubits` flag is set to False, you must insert [resets](/api/qiskit/qiskit.circuit.library.Reset) at the start of your circuit to start your qubits in the ground state. Otherwise, if your job consists of multiple circuits, the qubits will begin in their state from the previous shot. (If a job consists of multiple circuits, the shots will be executed in a "round-robin" fashion. That is, one shot will be collected from every circuit, and then the next shot will be collected from every circuit, and so on.)

The `init_qubits` flag controls whether qubits are reset to the zero state at the start of each circuit. Its default value is True, indicating that the qubits should be reset. If False, the qubits will begin in the final state from the previous shot, and you must manually insert [resets](/api/qiskit/qiskit.circuit.library.Reset) if you want to reset them to the zero state. If a job consists of multiple circuits, then the shots are executed in a "round-robin" fashion. That is, each circuit will be executed in sequence to obtain one shot from each circuit. This process is then repeated until the requested number of shots has been obtained from all circuits.

[kevinsung]

If we include this note, we have to mention what function the init_qubits flag is an argument of. A quick search of the source code suggests it is from assemble. But is this function even mentioned elsewhere in the docs?

[abbycross]

I see that it is also from execute(). I found this from API docs old release notes:

A new kwarg for init_qubits has been added to assemble() and execute(). For backends that support this feature init_qubits can be used to control whether the backend executing the circuits inserts any initialization sequences at the start of each shot. By default this is set to True meaning that all qubits can assumed to be in the ground state at the start of each shot. However, when init_qubits is set to False qubits will be uninitialized at the start of each experiment and between shots. Note, that the backend running the circuits has to support this feature for this flag to have any effect.)

[abbycross]

Also, the Conditional Reset page (which has been removed) had this pph:

Note: If init_qubits is set to false and you want qubits to start in the ground state, you must insert resets at the start of your circuit. Otherwise, qubits will begin with their state from the previous shot (after undergoing some thermalization process for the interval between shots as set by rep_delay). Note that the first shot of the first circuit may still be in the thermal ground state due to a longer delay existing during the loading of your job to hardware.

[abbycross]

So that's what I'm working with. Blake specifically mentioned the init_qubits flag, as long as it is supported by Sampler (which it is)... does it feel too much like it comes out of nowhere?

[kevinsung]

The note seems to presuppose that the user already knows about the init_qubits flag. Without further explanation, I would expect the init_qubits text to be a hyperlink pointing to a documentation page explaining its syntax, or to the function that has it as an argument. From reading the note, it's not clear to me in what sense the init_qubits flag is supported by Sampler. Is it Sampler(init_qubits=False)?

[beckykd]

From reading the note, it's not clear to me in what sense the init_qubits flag is supported by Sampler. Is it Sampler(init_qubits=False)?

You specify it as an execution option: ExecutionOptions(shots=4000, init_qubits=True https://docs.quantum.ibm.com/api/qiskit-ibm-runtime/qiskit_ibm_runtime.options.ExecutionOptions

[kevinsung]

Ah ok, the note should say that.

[javabster]

one of our goals is to have every docs page include a link to a learning platform topic where users can start using these concepts in practice, can you add a link to a sensible learning platform course/tutorial here please?

[abbycross]

How about the Submit transpiled circuits tutorial? Or we could do something broader like "Try one of the workflow example tutorials."