The CZ gate (or CPhase gate) is two-qubit operation defined as:
Note: For multi-qubit gates, it must always be checked whether the topology (connectivity) allows for a direct implementation of the operation. A compilation step may be required in order to map an operation.
As an example, on the Starmon-5 backend
q are not connected. An operation such as
cz q,q should therefore be rewritten as
cz q,q or compiled by inserting swap gates, when the intended operation is indeed a a cz between