Tighter monogamy and polygamy relations in multiqubit systems

Tighter monogamy relations of multiqubit entanglement in terms of Rényi-$α$ entanglement

“…and the power η > 2, we give a tighter monogamy relation with larger lower bounds than the result in [12,15,16]. Our result can provide a useful methodology to study further the monogamy properties of the multiparty quantum entanglement.…”

“…and the power η ≥ 2, where t = η 2 . We note that for η > 2, t = η 2 > 1, 1 + t 2 x + (2 t − t 2 − 1)x t > 1 + (2 t − 1)x t for all x ∈ (0, Lemma 4 and Lemma 5 give a tighter monogamy relation with larger lower bounds than the result in [12,15,16].…”

“…When α ≥ √ 7−1 2 , the squared Rényi-α entanglement satisfies the monogamy relations in N -qubit systems [12]. Recently, a class of tight monogamy relations were derived in multiqubit systems [13][14][15][16]. In this paper, we establish a class of tight monogamy relations of multiqubit entanglement in terms of Rényi-α entanglement related to the power of the Rényi-α entanglement, which are tighter than the results in [12,15,16].…”

Tighter monogamy relations of multiqubit entanglement in terms of Rényi-α entanglement

“…In particular, the monogamy relations are saturation for W-class states and this implies that this type of multipartite entanglement can be completely characterized [23,24]. Furthermore, a class of tight monogamy relations was derived by raising the power of the entanglement measures [25][26][27][28][29]. In this paper, we focus on tightening the monogamy relations in terms of Rényi-α entanglement by raising the power of the Rényi-α entanglement for multiqubit systems.…”

On Ergotropic Gap of Tripartite Separable Systems

“…As an essential kind of correlations, quantum entanglement plays an important role in quantum teleportation, quantum cryptography, quantum dense coding, quantum secret sharing and the development of quantum computer [19][20][21][22][23][24][25][26]. Distinguishing quantum entangled states from separable ones is of the significant but difficult problems in the theory of quantum entanglement.…”