Home | << 1 2 3 4 5 6 7 8 9 10 >> [11–20] |
Records | |||||
---|---|---|---|---|---|
Author | Baek, Burm; Lita, Adriana E.; Verma, Varun; Nam, Sae Woo | ||||
Title | Superconducting a-WxSi1–x nanowire single-photon detector with saturated internal quantum efficiency from visible to 1850 nm | Type | Journal Article | ||
Year | 2011 | Publication | Applied Physics Letters | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 98 | Issue | 25 | Pages | 3 |
Keywords | SNSPD | ||||
Abstract | We have developed a single-photon detector based on superconducting amorphous tungsten–silicon alloy (a-WxSi1–x) nanowire. Our device made from a uniform a-WxSi1–x nanowire covers a practical detection area (16 μm×16 μm) and shows high sensitivity featuring a plateau of the internal quantum efficiencies, i.e., efficiencies of generating an electrical pulse per absorbed photon, over a broad wavelength and bias range. This material system for superconducting nanowire detector technology could overcome the limitations of the prevalent nanowire devices based on NbN and lead to more practical, ideal single-photon detectors having high efficiency, low noise, and high count rates. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 665 | ||
Permanent link to this record | |||||
Author | Tanner, M. G.; Natarajan, C. M.; Pottapenjara, V. K.; O'Connor, J. A.; Warburton, R. J.; Hadfield, R. H.; Baek, B.; Nam, S.; Dorenbos, S. N.; Bermúdez Ureña, E.; Zijlstra, T.; Klapwijk, T. M.; Zwiller, V. | ||||
Title | Enhanced telecom wavelength single-photon detection with NbTiN superconducting nanowires on oxidized silicon | Type | Journal Article | ||
Year | 2010 | Publication | Applied Physics Letters | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 96 | Issue | 22 | Pages | 3 |
Keywords | SNSPD | ||||
Abstract | Superconducting nanowire single-photon detectors (SNSPDs) have emerged as a highly promising infrared single-photon detector technology. Next-generation devices are being developed with enhanced detection efficiency (DE) at key technological wavelengths via the use of optical cavities. Furthermore, new materials and substrates are being explored for improved fabrication versatility, higher DE, and lower dark counts. We report on the practical performance of packaged NbTiN SNSPDs fabricated on oxidized silicon substrates in the wavelength range from 830 to 1700 nm. We exploit constructive interference from the SiO2/Si interface in order to achieve enhanced front-side fiber-coupled DE of 23.2 % at 1310 nm, at 1 kHz dark count rate, with 60 ps full width half maximum timing jitter. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 655 | ||
Permanent link to this record | |||||
Author | Yamashita, Taro; Miki, Shigehito; Qiu, Wei; Fujiwara, Mikio; Sasaki, Masahide; Wang, Zhen | ||||
Title | Temperature dependent performances of superconducting nanowire single-photon detectors in an ultralow-temperature region | Type | Journal Article | ||
Year | 2010 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
Volume | 21 | Issue | 3 | Pages | 336 - 339 |
Keywords | SNSPD | ||||
Abstract | We report on the performance of a fiber-coupled superconducting nanowire single-photon detector (SNSPD) from 4 K down to the ultralow temperature of 16 mK for a 1550 nm wave length. The system detection efficiency (DE) increased with de creasing the temperature and reached the considerably high value of 15% with a dark count rate less than 100 cps below 1.5 K, even without an optical cavity structure. We also observed saturation of the system DE in its bias current dependency at 16 mK, which indicates that the device DE of our SNSPD nearly reached intrinsic DE despite the device having a large active area of 20 μm × 20 μm. The dark count was finite even at 16 mK and the black body radiation becomes its dominant origin in the low temperatures for fiber-coupled devices. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 656 | ||
Permanent link to this record | |||||
Author | Marsili, Francesco; Najafi, Faraz; Dauler, Eric; Bellei, Francesco; Hu, Xiaolong; Csete, Maria; Molnar, Richard J.; Berggren, Karl K. | ||||
Title | Single-photon detectors based on ultranarrow superconducting nanowires | Type | Journal Article | ||
Year | 2011 | Publication | Nano Letters | Abbreviated Journal | Nano Lett. |
Volume | 11 | Issue | 5 | Pages | 2048–2053 |
Keywords | SNSPD | ||||
Abstract | We report efficient single-photon detection (η = 20% at 1550 nm wavelength) with ultranarrow (20 and 30 nm wide) superconducting nanowires, which were shown to be more robust to constrictions and more responsive to 1550 nm wavelength photons than standard superconducting nanowire single-photon detectors, based on 90 nm wide nanowires. We also improved our understanding of the physics of superconducting nanowire avalanche photodetectors, which we used to increase the signal-to-noise ratio of ultranarrow-nanowire detectors by a factor of 4, thus relaxing the requirements on the read-out circuitry and making the devices suitable for a broader range of applications. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 659 | ||
Permanent link to this record | |||||
Author | Yang, J.K.W.; Kerman, A.J.; Dauler, E.A.; Cord, B.; Anant, V.; Molnar, R.J.; Berggren, K.K. | ||||
Title | Suppressed critical current in superconducting nanowire single-photon detectors with high fill-factors | Type | Journal Article | ||
Year | 2009 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | |
Volume | 19 | Issue | 3 | Pages | 318-322 |
Keywords | SNSPD | ||||
Abstract | In this work we present a new fabrication process that enabled the fabrication of superconducting nanowire single photon detectors SNSPD with fill-factors as high as 88% with gaps between nanowires as small as 12 nm. This fabrication process combined high-resolution electron-beam lithography with photolithography. Although this work was motivated by the potential of increased detection efficiency with higher fill-factor devices, test results showed an unexpected systematic suppression in device critical currents with increasing fill-factor. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 677 | ||
Permanent link to this record | |||||
Author | Hu, Xiaolong; Zhong, Tian; White, James E.; Dauler, Eric A. Najafi, Faraz; Herder, Charles H.; Wong, Franco N. C.; Berggren, Karl K. | ||||
Title | Fiber-coupled nanowire photon counter at 1550 nm with 24% system detection efficiency | Type | Journal Article | ||
Year | 2009 | Publication | Optics Letters | Abbreviated Journal | Opt. Lett. |
Volume | 34 | Issue | 23 | Pages | 3607-3609 |
Keywords | SNSPD | ||||
Abstract | We developed a fiber-coupled superconducting nanowire single-photon detector system in a close-cycled cryocooler and achieved 24% and 22% system detection efficiencies at wavelengths of 1550 and 1315 nm, respectively. The maximum dark count rate was ~1000 counts/s. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 679 | ||
Permanent link to this record | |||||
Author | Kerman, Andrew J.; Yang, Joel K. W.; Molnar, Richard J.; Dauler, Eric A.; Berggren, Karl K. | ||||
Title | Electrothermal feedback in superconducting nanowire single-photon detectors | Type | Journal Article | ||
Year | 2009 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
Volume | 79 | Issue | 10 | Pages | 4 |
Keywords | SNSPD | ||||
Abstract | We investigate the role of electrothermal feedback in the operation of superconducting nanowire single-photon detectors (SNSPDs). It is found that the desired mode of operation for SNSPDs is only achieved if this feedback is unstable, which happens naturally through the slow electrical response associated with their relatively large kinetic inductance. If this response is sped up in an effort to increase the device count rate, the electrothermal feedback becomes stable and results in an effect known as latching, where the device is locked in a resistive state and can no longer detect photons. We present a set of experiments which elucidate this effect and a simple model which quantitatively explains the results. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 680 | ||
Permanent link to this record | |||||
Author | Stevens, Martin J.; Baek, Burm; Dauler, Eric A.; Kerman, Andrew J.; Molnar, Richard J.; Hamilton, Scott A.; Berggren, Karl K.; Mirin, Richard P.; Nam, Sae Woo | ||||
Title | High-order temporal coherences of
chaotic and laser light | Type | Journal Article | ||
Year | 2010 | Publication | Optics Express | Abbreviated Journal | Opt. Express |
Volume | 18 | Issue | 2 | Pages | 1430-1437 |
Keywords | SNSPD | ||||
Abstract | We demonstrate a new approach to measuring high-order temporal coherences that uses a four-element superconducting nanowire single-photon detector. The four independent, interleaved single-photon-sensitive elements parse a single spatial mode of an optical beam over dimensions smaller than the minimum diffraction-limited spot size. Integrating this device with four-channel time-tagging electronics to generate multi-start, multi-stop histograms enables measurement of temporal coherences up to fourth order for a continuous range of all associated time delays. We observe high-order photon bunching from a chaotic, pseudo-thermal light source, measuring maximum third- and fourth-order coherence values of 5.87 ± 0.17 and 23.1 ± 1.8, respectively, in agreement with the theoretically predicted values of 3! = 6 and 4! = 24. Laser light, by contrast, is confirmed to have coherence values of approximately 1 for second, third and fourth orders at all time delays. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | SSPD | Approved | no | ||
Call Number | RPLAB @ gujma @ | Serial | 685 | ||
Permanent link to this record | |||||
Author | Bulaevskii, L. N.; Graf, Matthias J.; Kogan, V. G. | ||||
Title | Vortex-assisted photon counts and their magnetic field dependence in single-photon superconducting detectors | Type | Journal Article | ||
Year | 2012 | Publication | Phys. Rev. B | Abbreviated Journal | Phys. Rev. B |
Volume | 85 | Issue | 1 | Pages | 9 |
Keywords | SSPD; SNSPD; single-vortex crossing; normal-state belt | ||||
Abstract | We argue that photon counts in a superconducting nanowire single-photon detector (SNSPD) are caused by the transition from a current-biased metastable superconducting state to the normal state. Such a transition is triggered by vortices crossing the thin and narrow superconducting strip from one edge to another due to the Lorentz force. Detector counts in SNSPDs may be caused by three processes: (a) a single incident photon with sufficient energy to break enough Cooper pairs to create a normal-state belt across the entire width of the strip (direct photon count), (b) thermally induced single-vortex crossing in the absence of photons (dark count), which at high-bias currents releases the energy sufficient to trigger the transition to the normal state in a belt across the whole width of the strip, and (c) a single incident photon of insufficient energy to create a normal-state belt but initiating a subsequent single-vortex crossing, which provides the rest of the energy needed to create the normal-state belt (vortex-assisted single-photon count). We derive the current dependence of the rate of vortex-assisted photon counts. The resulting photon count rate has a plateau at high currents close to the critical current and drops as a power law with high exponent at lower currents. While the magnetic field perpendicular to the film plane does not affect the formation of hot spots by photons, it causes the rate of vortex crossings (with or without photons) to increase. We show that by applying a magnetic field one may characterize the energy barrier for vortex crossings and identify the origin of dark counts and vortex-assisted photon counts. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ gujma @ | Serial | 733 | ||
Permanent link to this record | |||||
Author | Henrich, D.; Dorner,S.; Hofherr, M.; Il'in, K.; Semenov, A.; Heintze, E.; Scheffler, M.; Dressel, M.; Siegel, M. | ||||
Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | Type | Journal Article | ||
Year | 2012 | Publication | Abbreviated Journal | J. Appl. Phys. | |
Volume | 112 | Issue | Pages | ||
Keywords | SSPD, SNSPD, magnetron sputtering, spectrum, NbN film, nitrogen concentration | ||||
Abstract | The spectral detection efficiency and the dark count rate of superconducting nanowire single-photon detectors (SNSPD) have been studied systematically on detectors made from thin NbN films with different chemical compositions. Reduction of the nitrogen content in the 4 nm thick NbN films results in a decrease of the dark count rates more than two orders of magnitude and in a red shift of the cut-off wavelength of the hot-spot SNSPD response. The observed phenomena are explained by an improvement of uniformity of NbN films that has been confirmed by a decrease of resistivity and an increase of the ratio of the measured critical current to the depairing current. The latter factor is considered as the most crucial for both the cut-off wavelength and the dark count rates of SNSPD. Based on our results we propose a set of criteria for material properties to optimize SNSPD in the infrared spectral region. VC 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757625] |
||||
Address | |||||
Corporate Author | D. Henrich, S. Dorner, M. Hofherr, K. Il'in, A. Semenov, E. Heintze, M. Scheffler, M. Dressel, M. Siegel | Thesis | |||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | Broadening of hot-spot response spectrum of superconducting NbN nanowire single-photon detector with reduced nitrogen content | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | RPLAB @ seleznev @ | Serial | 877 | ||
Permanent link to this record |