An Attempt to Derandomize the Random Unitary Matrices Used for Decoupling in Quantum Information Theory



Monday, 8 December 2014, 12:00 to 13:00


  • D-406 (D-Block Conference Room)


Abstract: The correlation of a quantum system $A$ to an initially correlated system $E$ generally decreases when $A$ undergoes an evolution separated from $E$. Here we study the conditions under which the correlation disappears completely, resulting in a decoupling of $A$ from $E$. Decoupling is a general way to prove many coding theorems in quantum information theory. However existing decoupling constructions use random unitaries which are inefficient to implement. Hence the quest for derandomization.