论文标题
蓝宝石基材上的高质量超导NB共同平面谐振器
High quality superconducting Nb co-planar resonators on sapphire substrate
论文作者
论文摘要
我们介绍了蓝宝石基材上的NB共同平面波导谐振器的测量和模拟，并以不同的读数功率降低到Millikelvin温度范围。在高温方案中，我们证明了NB膜残留的表面电阻与在超高质量，大量NB NB 3D超导射频腔中观察到的电阻相当，而谐振器质量由BCS热兴奋的准粒子主导。在低温下，使用两级系统模型可以很好地解释谐振器质量因子和频率。通过能量参与率模拟，我们发现两级系统损失切线为$ \ sim 10^{ - 2} $，它与在NB 3D腔中进行的类似研究非常吻合。
We present measurements and simulations of superconducting Nb co-planar waveguide resonators on sapphire substrate down to millikelvin temperature range with different readout powers. In the high temperature regime, we demonstrate that the Nb film residual surface resistance is comparable to that observed in the ultra-high quality, bulk Nb 3D superconducting radio frequency cavities while the resonator quality is dominated by the BCS thermally excited quasiparticles. At low temperature both the resonator quality factor and frequency can be well explained using the two-level system models. Through the energy participation ratio simulations, we find that the two-level system loss tangent is $\sim 10^{-2}$, which agrees quite well with similar studies performed on the Nb 3D cavities.
