01/02/16 15:30H Talk @ UFRJ – Kavan Modi – Monash University, AustraliaPosted: January 25, 2016
Title: Full and efficient characterisation of non-Markovian quantum processes
While Markov processes play an important role in physics, a Markov process is almost always an idealisation. In reality most processes are (at least slightly) non-Markovian. Yet, since the early days of quantum mechanics it has been a challenge to describe non-Markovian processes. Here we will show that using operational tools from quantum information theory we can fully characterise any non-Markovian process. In general the full characterisation is not efficient, as it requires exponentially large number of experiments. To overcome this obstacle we map the full process to a many-body state. We show that this can be achieved by using linear, in the number of time steps, amount of bipartite entanglement. This many-body state can be measured to any desired precision, thus the process can be characterised to any desired precision. Finally, we define a natural measure for the degree of non-Markovianity that has operational interpretation of distinguishing a Markov model for a non-Markovian process.
UFRJ- Centro de Tecnologia do Fundão, Bloco A, sala 343