. Pontificia Universidad Católica de Chile
The generalised quantum Harmonic oscillator and its decoherence-free sub-algebra
We consider the definition of the generalised Quantum Harmonic Oscillator (QHO) introduced by Bath and Parthasarathy in . It is well-known (see ) that all QMS suffers decoherence in its evolution. Loosely speaking, one says that "the quantum evolution becomes classical", this means that after some time, the dynamics concentrates on a commutative sub-algebra of observables. In  we characterized decoherence-free subalgebras where the evolution preserves its quantum structure. In general, these sub-algebras are trivial, nevertheless some physical systems do contain non trivial decoherence sub-algebras. More precisely, the decoherence-free subalgebra is the biggest (non commutative) where the semigroup act as a group of endomorphisms. The conference will show that the generalised QHO has a non trivial decoherence-free subalgebra.
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