It would be inappropriate for a President (any President) to ask a Justice to retire or resign. The President does not have the power to break up a Circuit.
The President can propose that a Circuit be broken up, but that would require a law to be passed.
Judges have been impeached and convicted, but I'm not sure that a Supreme Court Justice has ever been impeached, let alone convicted.
1 has been impeached, though not convicted, and the charges were drawn up at the request of the President... https://en.wikipedia.org/wiki/Samuel_Chase#Impeachment