Licentiate Thesis: Quantum Random Access Codes and their Applications
by
Alley Hameedi(Stockholm University, Department of Physics)
→
Europe/Stockholm
C5:1007
C5:1007
Description
Based on the principles of quantum mechanics, quantum information is a highly interesting
and fast emerging field which refers to processing information encoded into the state of a
quantum system and the subsequent use of such quantum systems for various information
tasks. In this thesis, we have studied the role of single d-level quantum systems (qudits) as a
quantum resource in the context of a communication task, commonly known as random
access codes (RACs). We investigate the advantage of quantum random access codes
(QRACs), employing quantum systems of arbitrary dimensions as means of communication
between the parties, in terms of average performances over their classical counterparts. For
this purpose, a class of QRACs with dimension d=4 is focused upon. Additionally, these
higher dimensional QRACs have also been studied in terms of applications where we consider
their potential in generation of true randomness. Furthermore, a parallel implementation of
two parallel QRACs (employing qubits) is explored as a resource for test of non-classicality
of a physical system.
Our results obtained show that QRACs outperform their classical counterparts performance
wise. Moreover, this advantage over classical resources can be extended further by use of
higher dimensional QRACs. The high-level QRACs lead to higher average success
probabilities and more generated randomness as compared to classical RACs or QRACs of
lower dimensions. Finally, an experimental test of non-classicality is demonstrated which
allows for arbitrarily low detection efficiencies and does not invoke extra assumptions as lack
of shared randomness between devices.
