When two operators A and B do not commute, the calculation of the exponential operator exp(A+B) is a difficult and crucial problem. The applications are vast and diversified: to name but a few examples, quantum evolutions, product formulas, quantum control, Zeno effect. The latter are of great interest in quantum applications and quantum technologies. We present here a historical survey of results and techniques, and discuss differences and similarities. We also highlight the link with the strong coupling regime, via the adiabatic theorem, and contend that the “pulsed” and “continuous” formulations differ only in the order by which two limits are taken, and are but two faces of the same coin.
Kick and Fix: The Roots of Quantum Control
Facchi, Paolo;Pascazio, Saverio
2019-01-01
Abstract
When two operators A and B do not commute, the calculation of the exponential operator exp(A+B) is a difficult and crucial problem. The applications are vast and diversified: to name but a few examples, quantum evolutions, product formulas, quantum control, Zeno effect. The latter are of great interest in quantum applications and quantum technologies. We present here a historical survey of results and techniques, and discuss differences and similarities. We also highlight the link with the strong coupling regime, via the adiabatic theorem, and contend that the “pulsed” and “continuous” formulations differ only in the order by which two limits are taken, and are but two faces of the same coin.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
