低通、带通电路在超导磁通量子比特测量中的应用  

Applications of Low-Pass and Band-Pass Circuits in Measuring the Superconductor Flux Qubit

作　　者：曹俊宇[1] 孙国柱[1] 王轶文[1] 丛山桦[1] 陈健[1] 于扬[1] 吴培亨[1] 

机构地区：[1]南京大学超导电子学研究所,江苏南京210093

出　　处：《稀有金属材料与工程》2008年第A04期453-456,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(10704034;10534060);国家"863"(2006AA03Z214);国家"973"(2006CB601006)

摘　　要：在测量超导磁通量子比特信息时,给出了低通和带通两种测量电路。低通电路采用双绞线,通过RC滤波器、铜粉滤波器,再接到样品上。该方法可以用于测量DC-SQUID结的跳变电流统计分布,从而获知量子比特的信息。带通电路用微波同轴线作为导线,通过衰减器、铜粉滤波器到样品上,再通过电容接地。该方法可以用于测量超导量子比特的量子化能级、迟豫时间、Rabi振荡等特性。We used low-pass circuit and band-pass circuit to measure the superconductor flux qubit. The low-pass circuit consists of twist pair lines, RC filter, and Cu-powder filter. With the low-pass circuit, we can get the switching current distribution of DC-SQUID and then the information of the qubit. The band-pass circuit consists of microwave coaxial cable, attenuators, Cu-powder filter and capacitance. With the band-pass circuit, we can measure the quantized energy levels, relaxation time and Rabi oscillation in the superconductor qubit.

关 键 词：超导磁悬浮 涡旋电流(VC) 自然边界 超导透析技术 

分 类 号：O511.9[理学—低温物理]