# Class of Bell-diagonal entanglement witnesses in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mi mathvariant="double-struck">C</mml:mi><mml:mn>4</mml:mn></mml:msup><mml:mo>⊗</mml:mo><mml:msup><mml:mi mathvariant="double-struck">C</mml:mi><mml:mn>4</mml:mn></mml:msup></mml:mrow></mml:math>: Optimization and the spanning property

> Research article (Physical review. A/Physical review, A, 2022) · cited 10× · AI/ML

**Wikidata**: [openalex:W4225275303](https://www.wikidata.org/wiki/openalex:W4225275303)  
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