在极低温下,我们对基于Nb/AlOx/Nb约瑟夫森结构成的超导磁通量子比特进行了测量,从粒子在双势阱的分布率和磁通的关系曲线中,分析得到了低频磁通噪声强度SФ(1Hz).进一步我们测量了在不同温度下的SФ(1Hz),结果表明在49.4mK到400mK温度区间,SФ(1Hz)随温度呈平方关系增长.
We measured the superconducting flux qubit based on Nb/AlOx/Nb Josephson junctions at mK temperature. From the dependence of population in the double potential wells on the external flux, we obtained the low-frequency flux noise SФ (1 Hz) at 1 Hz. By varying the temperature from 49.4 mK to 400 rnK, we got that SФ (1 Hz) is a parabolic function of the temperature.