By employing Pauli measurements, we present some nonlinear steering criteria applicable for arbitrary two-qubit quantum systems and optimized ones for symmetric quantum states. These criteria provide sufficient conditions to witness steering, which can recover the previous elegant results for some well-known states. Compared with the existing linear steering criterion and entropic criterion, ours can certify more steerable states without selecting measurement settings or correlation weights, which can also be used to verify entanglement as all steerable quantum states are entangled.

中文翻译：

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任意二量子位量子系统的非线性操纵准则

通过使用保利测量，我们提出了适用于任意两个量子比特量子系统的非线性控制准则，以及针对对称量子态的优化准则。这些条件为见证转向提供了充分的条件，可以为某些知名州恢复先前的优美结果。与现有的线性转向准则和熵准则相比，我们的方法无需选择测量设置或相关权重即可证明更可转向的状态，当所有可转向的量子态都被缠绕时，还可用于验证纠缠。