Higher-dimensional orbital-angular-momentum-based quantum key distribution with mutually unbiased bases

Abstract

We present an experimental study of higher-dimensional quantum key distribution protocols based on mutually unbiased bases, implemented by means of photons carrying orbital angular momentum. We perform (d + 1) mutually unbiased measurements in a classical prepare and measure scheme and on a pair of entangled photons for dimensions ranging from d = 2 to 5. In our analysis, we pay attention to the detection efficiency and photon pair creation probability. As security measures, we determine from experimental data the average error rate, the mutual information shared between the sender and receiver and the secret key generation rate per photon. We demonstrate that increasing the dimension leads to an increased information capacity as well as higher key generation rates per photon up to a dimension of d = 4.

Self-healing of quantum entanglement after an obstruction

“…As such, the LG modes were first used to demonstrate OAM entanglement 5 . However, a variety of bases may also be used to demonstrate OAM entanglement, including Ince-Gaussian 6 , Bessel-Gaussian (BG) 7,8 as well as mutually unbiased bases derived from these sets 9,10 . The OAM modal basis defines an infinite-dimensional Hilbert space, allowing access to highdimensional entanglement 11 .…”

Three-particle hyper-entanglement: teleportation and quantum key distribution

“…However, in practice, due to the strong quantum correlation and non-locality [24][25][26][27][28], the entanglement based protocols are regarded more useful (for example, they have intrinsic randomness of the distributed key and extremely low probability of double photons). In recent years, entanglement in two degrees of freedom such as polarization and OAM has led to interesting applications in cryptography [29,30].…”

The transition from a coherent optical vortex to a Rankine vortex: beam contrast dependence on topological charge

“…Spatially coherent light beams containing phase singularities are used within optical physics, where their angular momentum and/or their annular intensity cross-section lead to interesting effects (1)(2)(3)(4). Of particular prominence are those beams with helical phase-fronts described by a term exp(i φ), where φ is the azimuthal angle within the beam and , the topological charge, is an integer describing the number of intertwined helical phase surfaces, i.e.…”