How entangled can two couples get

By A. Higuchi, A. Sudbery. 2000

189 citations recorded by the source corpus.

We describe a pure state of four qubits whose single-qubit density matrices are all maximally mixed and whose average entanglement as a system of two pairs of qubits appears to be maximal.

Subfields: Artificial Intelligence, Atomic and Molecular Physics, and Optics

View Paper: https://www.semanticscholar.org/paper/9fede91b50353a024e75f370977270f40d033ab5

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Artificial Intelligence

1. Ingemar Bengtsson
2. Karol Zyczkowski
3. Alexander A. Klyachko
4. Dardo Goyeneche

In Atomic and Molecular Physics, and Optics

1. Ingemar Bengtsson
2. Karol Zyczkowski
3. Alexander A. Klyachko
4. Dardo Goyeneche

Citations in the corpus

• Geometry of Quantum States: Index (2007, background): “7 Consider the following four-qubit pure states: (a) |GHZ4〉 = (|0000〉 + |1111〉)/√2, (b) |B4〉 = (1)2 [|0000〉 + |0111〉 + |1001〉 + |1110〉], (c) |C4〉 = (1)2 [|0000〉 + |1100〉 + |0011〉 − |1111〉], (d) a suitably enphased Dicke state [435], |HS〉 = [|0011〉 + |1100〉 + ω(|0101〉 + |1010〉) + ω2(|0110〉 + |1001〉)]”
• QUANTUM MARGINAL PROBLEM AND REPRESENTATIONS OF THE SYMMETRIC GROUP (2004, background): “There is no pure 4-qubit state with scalar bivariant margins [18].”
• Genuinely multipartite entangled states and orthogonal arrays (2014, background): “Investigation of highly entangled states of several qubits, initiated by Gisin and BechmannPasquinucci [7], was then continued in the specific case of four qubits by Higuchi and Sudbery [8].”