基于铌超导隧道结的亚毫米波直接检测器  

SUBMILLMETER-WAVE DIRECT DETECTORS WITH Nb-BASED SUPERCONDUCTING TUNNEL JUNCTIONS

作　　者：梁敏[1] 姜弈[1] 陈健[1] 吴培亨[1] 

机构地区：[1]南京大学超导电子学研究所,南京210093

出　　处：《低温物理学报》2010年第3期193-198,共6页Low Temperature Physical Letters

基　　金：国家自然科学基金(批准号:10778602和60721063);科技部973项目(批准号:2006CB601006);江苏省基金(批准号:BK2007713)资助的课题~~

摘　　要：基于铌(Nb)超导隧道结(STJ)的亚毫米波直接检测器可以达到宽频带响应,高灵敏度,适于组建大规模阵列的要求,满足亚毫米波段射电天文观测等应用领域的需求.本文设计了在650 GHz波段的约10%有效带宽的Nb STJ直接检测器,宽带耦合采用了分布式结阵列的方法,把多个同样尺寸的STJ用一根超导微带线串行连接.12个STJ在平面对数—周期天线的两翼组成2组6结阵列,构成一个检测器.通过对STJ阵列的详细分析,宽带所需要的N个谐振峰的结合需要N个短超导电感的双结通过N—1个长超导电感交替隔开.在液氦温度(4.2 K)下实际测量得到的检测器中心频率为655 GHz,带宽约50 GHz,直接检测的电流响应率约为1 A/W.Submillimeter-wave direct detectors employing niobium-based superconducting tunnel junctions（STJs） match the request of broadband spectral response and high sensitivity,and having capability of large format arrays. We aim to realize the fractional bandwidth of 10 percent（60 GHz） at 650 GHz.The broadband coupling was designed using 2 distributed junction（DJ） arrays,which were composed of six STJs connected in parallel by a superconducting microstrip line.By analyze the DJ arrays,we found N-resonance combination needs to connect N-set of twin-junctions with short inductances through（N—1）-long inductances,alternatively.And we got the experiment result at 4.2 K that the center frequency of the STJ is 655 GHz,bandwidth about 50GHz,and the sensitivity is 1A/ W.

关 键 词：超导隧道结 亚毫米波 结阵列 直接检测器 

分 类 号：O511[理学—低温物理]