{"id":1606,"date":"2013-07-25T18:30:31","date_gmt":"2013-07-25T18:30:31","guid":{"rendered":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/?p=1606"},"modified":"2013-08-05T19:31:25","modified_gmt":"2013-08-05T19:31:25","slug":"membrane-integrated-superconducting-nanowire-single-photon-detectors","status":"publish","type":"post","link":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/membrane-integrated-superconducting-nanowire-single-photon-detectors\/","title":{"rendered":"Membrane-integrated Superconducting Nanowire Single-photon Detectors"},"content":{"rendered":"
Fig. 1. (a) SEM of a SiNx membrane (~ 350-nm thick) with SNSPD on top. (b) Optical micrograph of a membrane-SNSPD that was transferred and aligned to a Si waveguide on a PIC chip. (c) Instrument response function (IRF) of a membrane-SNSPD transferred onto a secondary substrate. The IRF was measured using a mode-locked fiber-coupled laser with sub-ps-pulse-width and 1550-nm wavelength. We measured sub-35-ps timing jitter for detectors with IC > 13 \u03bcA.<\/p><\/div>\n
Superconducting nanowire single-photon detectors (SNSPDs)[1<\/a>]<\/sup> based on niobium nitride (NbN) nanowires have shown high speed (< 3ns dead time[2<\/a>]<\/sup> ) and timing resolution (sub-30-ps timing jitter[3<\/a>]<\/sup> ), making SNSPDs a leading single-photon detection technology in the near-infrared range.<\/p>\n Recently SNSPDs have attracted interest as components in photonic integrated circuits (PICs), which enable the generation, manipulation, and detection of non-classical photons on a single chip. Previous approaches to integrating SNSPDs with photonic structures[4<\/a>]<\/sup>[5<\/a>]<\/sup>[6<\/a>]<\/sup> were compatible with only a handful of substrate materials and required additional fabrication steps on the sample. These steps can be incompatible with complex and delicate PICs. Based on a micron-scale flip-chip concept[7<\/a>]<\/sup>, we have developed a technology that enables integration of SNSPDs on PICs without exposing the PIC to chemicals or high temperatures. We used this method to integrate SNSPDs with silicon waveguides designed for 1550-nm center wavelength.<\/p>\n NbN-SNSPDs based on sub-100-nm-wide nanowires were fabricated on top of a SiNx<\/sub>-on-Si substrate. The underlying silicon was removed via isotropic dry etch in XeF2<\/sub>, resulting in SNSPDs on suspended ~350-nm-thick SiNx<\/sub> membranes. The scanning electron micrograph (SEM) of a membrane-SNSPD is shown in Figure 1(a). Micro-manipulated tungsten probes were used to pick up the membrane and visually align it to the waveguide on the PIC chip. Figure 1(b) shows a membrane-SNSPD after transfer onto a waveguide.<\/p>\n Preliminary measurements on membrane-SNSPDs that were transferred on a secondary substrate showed that the contact between the membrane and the secondary substrate was sufficient to cool the detector in a continuous-flow cryostat, where we measured sub-35-ps timing jitter, as shown in Figure 1(c). While the photonic structures demonstrated here are waveguides, this technology could be applied to other PICs that require on-chip integration and near-field single-photon detection.<\/p>\n Superconducting nanowire single-photon detectors (SNSPDs)[1] based on niobium nitride (NbN) nanowires have shown high speed (< 3ns dead time[2] )…<\/p>\n","protected":false},"author":370,"featured_media":1607,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[6083,5532],"tags":[6116,41],"_links":{"self":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/1606"}],"collection":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/users\/370"}],"replies":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/comments?post=1606"}],"version-history":[{"count":4,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/1606\/revisions"}],"predecessor-version":[{"id":2373,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/posts\/1606\/revisions\/2373"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/media\/1607"}],"wp:attachment":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/media?parent=1606"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/categories?post=1606"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2013\/wp-json\/wp\/v2\/tags?post=1606"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}