Skip to content
DraconiticResearch
Search Sources API
203,203 studies31 sourcesUpdated 33 min ago
PreprintarXiv licencearXiv

Two-qubit binegativity can increase under local amplitude damping

Abstract

It has been conjectured that the binegativity of two-qubit states is an entanglement monotone. We present a full-rank state as a counterexample: applying amplitude damping to only one of the qubits can increase the binegativity of the state. The output state remains full rank, and the amount of increase can be calculated exactly. In addition, we construct a family of counterexamples that vary continuously with a parameter. In the corresponding one-way local operations and classical communication protocol, the probability-weighted average of the binegativity over the branches after the local measurement is also higher than that of the initial state.

Related

  1. Convergence Analysis of the Quantum Blahut-Arimoto Algorithm and the Contraction Coefficient of Qubit Amplitude-Damping Channels
    Junke Han, Yonglong Li
    arXivPreprintarXiv licenceFull textQuantum physics & quantum informationarXiv
  2. Exact series formulas for the capacities of the amplitude damping channel
    Stefano Pirandola
    arXivPreprintarXiv licenceFull textMathematical physicsOptics & photonicsarXiv
  3. The classical capacity of generalized amplitude-damping channels and its strong-converse exponent
    Kun Fang
    arXivPreprintarXiv licenceFull textGeneral mathematicsQuantum physics & quantum informationarXiv
  4. Quantum Codes for Generalized Amplitude-damping Noise
    Sourav Dutta, Anubhab Rudra, Manav Seksaria +2
    arXivPreprintCC BY 4.0Full textQuantum physics & quantum informationarXiv
  5. Classical Capacity and Entanglement Cost of the Amplitude Damping Channel
    Ziao Tang, Chengkai Zhu, Ge Bai +1
    arXivPreprintCC BY 4.0Full textQuantum physics & quantum informationarXiv
BibTeX
@misc{zong2026twoqubit,
  title = {{Two-qubit binegativity can increase under local amplitude damping}},
  author = {Xiao-Lan Zong and Wei Song and Ming Yang},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.34322},
  eprint = {2610.34322},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.34322},
}
RIS
TY  - UNPB
TI  - Two-qubit binegativity can increase under local amplitude damping
AU  - Xiao-Lan Zong
AU  - Wei Song
AU  - Ming Yang
PY  - 2026
DA  - 2026/10/25
PB  - arXiv
DO  - 10.48550/arxiv.2610.34322
UR  - https://arxiv.org/abs/2610.34322
AB  - It has been conjectured that the binegativity of two-qubit states is an entanglement monotone. We present a full-rank state as a counterexample: applying amplitude damping to only one of the qubits can increase the binegativity of the state. The output state remains full rank, and the amount of increase can be calculated exactly. In addition, we construct a family of counterexamples that vary continuously with a parameter. In the corresponding one-way local operations and classical communication protocol, the probability-weighted average of the binegativity over the branches after the local measurement is also higher than that of the initial state.
ER  -