A noise-spectrum analysis without spurious harmonics is developed and applied to a molecular qubit, which has complicated composition of spin bath. A type of molecular-qubit transition-metal complex $({\mathrm{PPh}}_4{)}_2[{\mathrm{Cu(mnt)}}_2]$ is utilized to demonstrate our method. Various types of nuclear spins in its spin bath, such as ${}^1\mathrm{H}$, ${}^{31}\mathrm{P}$, ${}^{13}\mathrm{C}$, and ${}^{63}\mathrm{Cu}$ are resolved with our method, while only the signal from ${}^1\mathrm{H}$ can be resolved by traditional noise-spectrum analysis. Our result provides a noise-spectrum analysis without spurious harmonics, which enables the design of optimal quantum-control methods, improves the material engineering, and generally enhances coherence for molecular qubits.

中文翻译：

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通过动态去耦的分子自旋量子比特噪声光谱

开发了一种无伪谐波的噪声谱分析，并将其应用于具有复杂自旋浴组成的分子量子位。一种分子-量子比特过渡金属配合物$({\mathrm{聚丙烯酰胺}}_4{)}_2[{\mathrm{铜(mnt)}}_2]$用于演示我们的方法。其自旋浴中的各种类型的核自旋，例如${}^1\mathrm{H}$, ${}^{31}\mathrm{磷}$, ${}^{13}\mathrm{C}$， 和 ${}^{63}铜$ 用我们的方法解决，而只有来自 ${}^1\mathrm{H}$可以通过传统的噪声频谱分析来解决。我们的结果提供了没有虚假谐波的噪声频谱分析，这使得设计最佳量子控制方法成为可能，改进了材料工程，并普遍增强了分子量子位的相干性。