Quantum Information Amplifiers

Quantum Information Amplifiers

Seminar author:Giulio Chiribella

Event date and time:07/16/2013 02:30:pm

Event location:Sala de Graus II (C5 building, Ciències UAB)

Event contact:

Quantum Information is a new paradigm of information processing, where the systems used to store, transmit, and process data obey the laws of quantum mechanics.  
One of the cornerstones of Quantum Information is the no-cloning theorem, stating that there exist no perfect “quantum copy machine”.   
In this talk I will present some attempts to go beyond the no-cloning theorem, considering quantum processes that produce approximate copies with the best accuracy allowed by the laws of quantum mechanics.  After introducing the fundamental features of approximate cloning processes, I will discuss how cloning can be treated as a special case of a more general task, the amplification of quantum signals. As a specific example, I will present a new result on the ultimate quantum limits to the amplification of coherent states of light, considering both deterministic and non-determinstic processes, and relating these limits to recent experimental breakthroughs on non-deterministic quantum optical amplification.