Details

Autor(en) / Beteiligte

• Nakazato, Hiromichi
• Sergi, Alessandro
• Migliore, Agostino
• Messina, Antonino

Titel

Invariant-Parameterized Exact Evolution Operator for SU (2) Systems with Time-Dependent Hamiltonian

Ist Teil von

• Entropy (Basel, Switzerland), 2023-01, Vol.25 (1), p.96

Ort / Verlag

Switzerland: MDPI AG

Erscheinungsjahr

2023

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• We report the step-by-step construction of the exact, closed and explicit expression for the evolution operator U(t) of a localized and isolated qubit in an arbitrary time-dependent field, which for concreteness we assume to be a magnetic field. Our approach is based on the existence of two independent dynamical invariants that enter the expression of SU(2) by means of two strictly related time-dependent, real or complex, parameters. The usefulness of our approach is demonstrated by exactly solving the quantum dynamics of a qubit subject to a controllable time-dependent field that can be realized in the laboratory. We further discuss possible applications to any SU(2) model, as well as the applicability of our method to realistic physical scenarios with different symmetry properties.