SEMINAR @ SISSSA, F. Ticozzi 18 April 2007 at 4.00 p.m.

[Barbara Corzani]

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FUNCTIONAL ANALYSIS SECTOR'S ACTIVITIES
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SEMINAR 

Dott. 
Francesco Ticozzi
(Università di Padova)


Title:
"Quantum Markovian Dynamics, Subsystems and Control: A System-Theoretic Perspective"

Wed. 18 April 2007  @  04.00 p.m.

SISSA - Main Building - ground floor - room B

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Abstract:
Any practical application of Quantum Information Processing (QIP) needs to 
encode, process and protect information in physical system with quantum 
behavior. Realistic models of a quantum system must account for the action of 
the environment (quantum noise). By assuming Markovian dynamics, i.e. a 
memoryless environment, we restrict our attention to a class of dynamical 
models that is well-suited for a system-theoretic analysis, based on 
linear-algebraic structures. This approach  will provide us with a 
characterization of invariant subsystems which are not affected by noise, hence 
representing protected realization of quantum information suitable for QIP. We 
will also introduce the notion of attractive subsystems and hence study under 
which conditions the noise drives the system in the subsystem of interest. If 
we further assume to have Hamiltonian open-loop and feedback control 
capabilities, we can employ the same linear-algebraic techniques to tackle 
feedback-stabilization problems and to design controlled dynamics that admit 
noiseless subsystems. The main robustness issues will be discussed, and results 
compared to other state-of-the-art strategies.