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Hybrid entangled states exhibit non-local correlations between photons with independent degrees of freedom and are currently gaining much interest. In particular, hybrid entanglement between polarisation and spatial modes of two photons are promising candidates for future heterogeneous quantum channels, but their versatility is limited by current generation methods that rely on static elements. Here, we present a technique that exploits polarisation and spatial mode dependent phase modulation in an all-digital approach using spatial light modulators. We show that we can tailor hybrid entangled states using spatial modes with Cylindrical and Cartesian symmetry, making our approach flexible, dynamic, and adaptable. [ABSTRACT FROM AUTHOR]

In the present article we report the dynamics of electronic spin-subbands, as well as subband-subband, hybrid entanglements in a two-dimensional anisotropic quantum dot. The dot is under the influence of Rashba effect and an external magnetic field. To study the hybrid entanglements, we partition the system into two categories in which either spatial degrees of freedom, subbands, entangle with the spin or the subbands become entangled amongst themselves. For the first case we calculate the von Neumann entropy, while for the latter the negativity is calculated. Our calculations show that for both cases information is periodically distributed between the corresponding subspaces. Effects of Rashba parameter and magnetic field on the characteristics of such oscillatory behavior are also discussed. For spin-subband entanglement the oscillations include dips, surrounded by plateaus of maximal entanglement. The subband-subband entanglement shows vanishingly small plateaus. The duration of plateaus is controlled by Rashba coupling and the external field. [ABSTRACT FROM AUTHOR]

Abstract: A novel quantum key distribution scheme based on the path-spin hybrid entanglement is proposed and analyzed. In this proposed scheme, the entanglement between the path and the spin degrees of freedom is confined locally with the single particle and transmitted in one-way direction. Two split pulses of a single spin-1/2 particle are not simultaneously transmitted through the public quantum channels for the security goal. The scheme is robust against any individual attack even in noisy environments. Moreover, it also has high-efficiency since one single particle can be used to generate one bit key on average. [ABSTRACT FROM AUTHOR]