Hyperentanglement concentration for time-bin and polarization hyperentangled photons

Abstract

We present two hyperentanglement concentration schemes for two-photon states that are partially entangled in the polarization and time-bin degrees of freedom. The first scheme distills a maximally hyperentangled state from two identical less-entangled states with unknown parameters via the Schmidt projection method. The other scheme can be used to concentrate an initial state with known parameters, and requires only one copy of the initial state for the concentration process. Both these two protocols can be generalized to concentrate N -photon hyperentangled GreenbergerHorne-Zeilinger states that are simultaneously entangled in the polarization and time-bin degrees of freedom. Our schemes require only linear optics and are feasible with current technology. Using the time-bin degree of freedom rather than the spatial mode degree of freedom can provide savings in quantum resources, which makes our schemes practical and useful for long-distance quantum communication.

Complete hyperentangled Bell state analysis for polarization and time-bin hyperentanglement

“…It is also a simple and conventional classical DOF of photons, and can be simply discriminated by the time of arrival. Despite the difficulties in manipulation of time-bin DOF, we have previously proposed a hyperentanglement concentration scheme for polarization and time-bin hyperentanglement [36]. Here, we propose the first complete HBSA scheme for polarization and time-bin hyperentangled states.…”

“…Hyperentangled states have also been used to accomplish deterministic entanglement purification of polarization entanglement [22][23][24][25], construct hyperparallel photonic quantum computing [26,27] and quantum repeaters [28]. Entanglement concentration and entanglement purification protocols for hyperentangled state have also been proposed with the aim of establishing maximally hyperentangled channels between distant parties [29][30][31][32][33][34][35][36].…”

General hyperconcentration of photonic polarization-time-bin hyperentanglement assisted by nitrogen-vacancy centers coupled to resonators

“…It can increase the channel capacity of quantum communication2021222324, achieve the complete Bell-state analysis for the quantum states in the polarization DOF11, be used to teleport the unknown quantum state in two DOFs21 and complete the hyperentanglement swapping between two photonic quantum systems without entanglement22, and help to design the deterministic hyperentanglement purification11121314 which solves the troublesome problem that the parties in quantum repeaters should sacrifice a large amount of quantum resources with conventional entanglement purification protocols (EPPs)910 as the deterministic EPPs11121314 work in a completely deterministic way252627. Recently, some interesting hyperentanglement concentration protocols (hyper-ECPs)2829303132333435 were proposed. For example, in 2013, Ren et al 28 proposed the first hyper-ECP for two-photon systems in polarization-spatial less-hyperentangled states with linear optical elements only, including the cases for the nonlocal photonic quantum systems with known and unknown parameters, respectively.…”

Minimal control power of the controlled teleportation

“…Recently, Li and Ghose [10] investigated a control power of the controller in perfect CT via two classes of the partially entangled three-qubit pure states, and generalized it to multiqubit CT schemes [11]. In this paper, we define a minimal control power of the CT, which is a more general concept compared to the perfect case in Refs.…”

“…In this paper, we define a minimal control power of the CT, which is a more general concept compared to the perfect case in Refs. [10,11], and we present explicit calculations for the minimal control power for a class of general threequbit GHZ states and the three-qubit W class whose states have zero three-tangles. Moreover, we show that the standard GHZ state and the standard W state have the maximal values of the minimal control power for the two classes, respectively.…”