Relatore: Dr Paolo Zanardi
ISI - Institute for Scientific Interchange - Torino

Aula Einstein
12 Febbraio 2002 - Ore 15.30


Stabilizing  quantum-information   processing against 
the environmental interactions as well as operation 
imperfections is a vital goal for any practical application 
of the protocols  of Quantum Information and Quantum 
Computation theory. We  show how all the stabilizing 
schemes developed to the date  derive conceptually from 
a unified dynamical-algebraic framework.
Such a  framework allows  to build systematically new 
classes of error correcting codes and noiseless subsystems. 
When the required symmetries are non present one can in 
principle - by using  symmetrization techniques - 
artificially produce noiseless subsystems. 
These noiseless sectors are shown to support universal 
quantum computation and to be robust against perturbations.
We shall discuss the general theory of such "Noiseless 
Quantum Codes" and its application to quantum information-
encoding in realistic semiconductor-based nanostructures.