Implement frequency changes for pulse

What is the expected enhancement?

PulseChannels create the control fields Re[exp(i 2pi j dt f + phi)d_j]. There should be a Command to change the frequency f of the PulseChannel.

This instruction will be implemented by class SetChannelFrequency(Command). It will have

• one attribute, the new frequency of the channel, i.e. self._frequency,
• the prefix scf,
• and will result in the command_dict {‘name’: ‘scf’, ‘t0’: …, ‘ch’: …, ‘frequency’: … }

[eggerdj]

Thinking about this a bit more I am now comfortable with SetFrequency. Changing the qubit frequency for a fixed duration T would require a square pulse (implemented as ConstantPulse(ParametricPulse) or SamplePulse) of duration T on the flux bias line. (If the frequency change is to be until the end of the schedule then a persistent value would probably better). At this point its up to the user to know that his square pulse will change the frequency of the qubit.

[eggerdj]

@taalexander Yes I’ll implement this. Please assign me.

SetFrequency is also an option and it makes sense given that Commands are applied on channels. My reason for making channel explicit is that for flux-tunable qubits I can imagine a command named SetQubitFrequency. I.e. to avoid any ambiguity I would prefer to have SetChannelFrequency.