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Author Zubkova, E.; An, P.; Kovalyuk, V.; Korneev, A.; Ferrari, S.; Pernice, W.; Goltsman, G.
Title Optimization of contra-directional coupler based on silicon nitride Bragg rib waveguide Type Conference Article
Year 2018 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1124 Issue Pages 051048
Keywords Bragg waveguide, Si3N4
Abstract We report on the development and fabrication of a contra-directional coupler based on the Bragg waveguide on Si3N4 platform. Transmitted and reflected by the contra-directional coupler spectra were measured. The reflected spectra exactly matches the one notched by the main channel of the coupler. Losses are about 3dB, coupling to the directing branch of the coupler is practically lossless. FWHM of the transmitted (reflected) spectra is 3.46 nm.
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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 1742-6588 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1195
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Author Prokhodtsov, A.; An, P.; Kovalyuk, V.; Zubkova, E.; Golikov, A.; Korneev, A.; Ferrari, S.; Pernice, W.; Goltsman, G.
Title Optimization of on-chip photonic delay lines for telecom wavelengths Type Conference Article
Year 2018 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1124 Issue Pages 051052
Keywords optical delay lines
Abstract In this work, we experimentally studied optical delay lines on silicon nitride platform for telecomm wavelength (1550 nm). We modeled the group delay time and fabricated spiral optical delay lines with different waveguide widths and radii as well as measured their transmission. For the half etched rib waveguides we achieved the losses in the range of 3 dB/cm.
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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 1742-6588 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1196
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Author Kovalyuk, V.; Kahl, O.; Ferrari, S.; Vetter, A.; Lewes-Malandrakis, G.; Nebel, C.; Korneev, A.; Goltsman, G.; Pernice, W.
Title On-chip single-photon spectrometer for visible and infrared wavelength range Type Conference Article
Year 2018 Publication J. Phys.: Conf. Ser. Abbreviated Journal J. Phys.: Conf. Ser.
Volume 1124 Issue Pages 051045
Keywords single-photon spectrometer
Abstract Here we show our latest progress in the field of a single-photon spectrometer for the visible and infrared wavelengths ranges implementation. We consider three different on-chip approaches: a coherent spectrometer with a low power of the heterodyne, a coherent spectrometer with a high power of the heterodyne, and an eight-channel single-photon spectrometer for direct detection. Along with high efficiency, spectrometers show high detection efficiency and temporal resolution through the use of waveguide integrated superconducting nanowire single-photon detectors.
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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 1742-6588 ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1197
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Author Korneev, A.; Kovalyuk, V.; An, P.; Golikov, A.; Zubkova, E.; Ferrari, S.; Kahl, O.; Pernice, W.; Goltsman, G.; Naumov, A. V.; Gladush, M. G.; Karimullin, K. R.
Title Superconducting single-photon detector for integrated waveguide spectrometer Type Conference Article
Year 2018 Publication EPJ Web Conf. Abbreviated Journal EPJ Web Conf.
Volume 190 Issue Pages 04009
Keywords SSPD, SNSPD, Si3N4 waveguides, waveguide spectrometer
Abstract We present our recent achievements in the development of an on-chip spectrometer consisting of arrayed waveguide grating made of Si3N4 waveguides and NbN superconducting single-photon detector.
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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 2100-014X ISBN Medium
Area Expedition Conference
Notes (up) Approved no
Call Number Serial 1199
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Author Trifonov, A.; Tong, C.-Y. E.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G.
Title Gap frequency and photon absorption in a hot electron bolometer Type Conference Article
Year 2016 Publication Proc. 27th Int. Symp. Space Terahertz Technol. Abbreviated Journal Proc. 27th Int. Symp. Space Terahertz Technol.
Volume Issue Pages 121
Keywords NbN HEB; Si membrane
Abstract The superconducting energy gap is a crucial parameter of a superconductor when used in mixing applications. In the case of the SIS mixer, the mixing process is efficient for frequencies below the energy gap, whereas, in the case of the HEB mixer, the mixing process is most efficient at frequencies above the gap, where photon absorption takes place more readily. We have investigated the photon absorption phenomenon around the gap frequency of HEB mixers based on NbN films deposited on silicon membranes. Apart from studying the pumped I-V curves of HEB devices, we have also probed them with microwave radiation, as previously described [1]. At frequencies far below the gap frequency, the pumped I-V curves show abrupt switching between the superconducting and resistive states. For the NbN HEB mixers we tested, which have critical temperatures of ~9 K, this is true for frequencies below about 400 GHz. As the pump frequency is increased beyond 400 GHz, the resistive state extends towards zero bias and at some point a small region of negative differential resistance appears close to zero bias. In this region, the microwave probe reveals that the device impedance is changing randomly with time. As the pump frequency is further increased, this random impedance change develops into relaxation oscillations, which can be observed by the demodulation of the reflected microwave probe. Initially, these oscillations take the form of several frequencies grouped together under an envelope. As we approach the gap frequency, the multiple frequency relaxation oscillations coalesce into a single frequency of a few MHz. The resultant square-wave nature of the oscillation is a clear indication that the device is in a bi-stable state, switching between the superconducting and normal state. Above the gap frequency, it is possible to obtain a pumped I-V curve with no negative differential resistance above a threshold pumping level. Below this pumping level, the device demonstrates bi-stability, and regular relaxation oscillation at a few MHz is observed as a function of pump power. The threshold pumping level is clearly related to the amount of power absorbed by the device and its phonon cooling. From the above experiment, we can derive the gap frequency of the NbN film, which is 585 GHz for our 6 μm thin silicon membrane-based device. We also confirm that the HEB mixer is not an efficient photon absorber for radiation below the gap frequency. 1. A. Trifonov et al., “Probing the stability of HEB mixers with microwave injection”, IEEE Trans. Appl. Supercond., vol. 25, no. 3, June 2015.
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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 (up) Approved no
Call Number Serial 1204
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