[Seminar] High-dimensional entanglement witnessed by correlations in arbitrary bases

Speaker

Nicky Kai Hong Li, Technical University of Vienna (Austria)

Title

High-dimensional entanglement witnessed by correlations in arbitrary bases

Abstract

Certifying entanglement is an important step in the development of many quantum technologies, especially for higher-dimensional systems, where entanglement promises increased capabilities for quantum communication and computation. A key feature distinguishing entanglement from classical correlations is the occurrence of correlations for complementary measurement bases. In particular, mutually unbiased bases (MUBs) are a paradigmatic example that is well-understood and routinely employed for entanglement certification. However, implementing unbiased measurements exactly is challenging and not generically possible for all physical platforms. In this work, we expand the entanglement-certification toolbox by extending the use of correlations in MUBs to arbitrary bases, even without requiring aligned reference frames. This represents a practically significant simplification that paves the way for the efficient characterization of high-dimensional entanglement in a wide range of physical systems. In my talk, I will also discuss the potential of using approximately MUBs (AMUBs) or even random measurement bases to detect high-dimensional entanglement. As a bonus, I will present a new, simple construction of three MUBs that exist in any dimension without resorting to the tensor products of the Wootters-Fields construction.

Contact details: bill.munro@oist.jp