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| Author | Vorobyov, V. V.; Kazakov, A. Y.; Soshenko, V. V.; Korneev, A. A.; Shalaginov, M. Y.; Bolshedvorskii, S. V.; Sorokin, V. N.; Divochiy, A. V.; Vakhtomin, Y. B.; Smirnov, K. V.; Voronov, B. M.; Shalaev, V. M.; Akimov, A. V.; Goltsman, G. N. | ||||
| Title | Superconducting detector for visible and near-infrared quantum emitters [Invited] | Type | Journal Article | ||
| Year | 2017 | Publication | Opt. Mater. Express | Abbreviated Journal | Opt. Mater. Express |
| Volume | 7 | Issue | 2 | Pages | 513-526 |
| Keywords | SSPD, SNSPD | ||||
| Abstract | Further development of quantum emitter based communication and sensing applications intrinsically depends on the availability of robust single-photon detectors. Here, we demonstrate a new generation of superconducting single-photon detectors specifically optimized for the 500–1100 nm wavelength range, which overlaps with the emission spectrum of many interesting solid-state atom-like systems, such as nitrogen-vacancy and silicon-vacancy centers in diamond. The fabricated detectors have a wide dynamic range (up to 350 million counts per second), low dark count rate (down to 0.1 counts per second), excellent jitter (62 ps), and the possibility of on-chip integration with a quantum emitter. In addition to performance characterization, we tested the detectors in real experimental conditions involving nanodiamond nitrogen-vacancy emitters enhanced by a hyperbolic metamaterial. | ||||
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| ISSN | 2159-3930 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1234 | |||
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| Author | Kahl, O.; Ferrari, S.; Kovalyuk, V.; Vetter, A.; Lewes-Malandrakis, G.; Nebel, C.; Korneev, A.; Goltsman, G.; Pernice, W. | ||||
| Title | Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits | Type | Journal Article | ||
| Year | 2017 | Publication | Optica | Abbreviated Journal | Optica |
| Volume | 4 | Issue | 5 | Pages | 557-562 |
| Keywords | Waveguide integrated superconducting single-photon detectors; Nanophotonics and photonic crystals; Quantum detectors; Spectrometers and spectroscopic instrumentation | ||||
| Abstract | The detection of individual photons by superconducting nanowire single-photon detectors is an inherently binary mechanism, revealing either their absence or presence while concealing their spectral information. For multicolor imaging techniques, such as single-photon spectroscopy, fluorescence resonance energy transfer microscopy, and fluorescence correlation spectroscopy, wavelength discrimination is essential and mandates spectral separation prior to detection. Here, we adopt an approach borrowed from quantum photonic integration to realize a compact and scalable waveguide-integrated single-photon spectrometer capable of parallel detection on multiple wavelength channels, with temporal resolution below 50 ps and dark count rates below 10 Hz at 80% of the devices' critical current. We demonstrate multidetector devices for telecommunication and visible wavelengths, and showcase their performance by imaging silicon vacancy color centers in diamond nanoclusters. The fully integrated hybrid superconducting nanophotonic circuits enable simultaneous spectroscopy and lifetime mapping for correlative imaging and provide the ingredients for quantum wavelength-division multiplexing on a chip. | ||||
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| Notes | Approved | no | |||
| Call Number | RPLAB @ kovalyuk @ | Serial | 1119 | ||
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| Author | Kahl, O.; Ferrari, S.; Kovalyuk, V.; Vetter, A.; Lewes-Malandrakis, G.; Nebel, C.; Korneev, A.; Goltsman, G.; Pernice, W. | ||||
| Title | Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits: supplementary material | Type | Miscellaneous | ||
| Year | 2017 | Publication | Optica | Abbreviated Journal | |
| Volume | Issue | Pages | 1-9 | ||
| Keywords | Quantum detectors; Spectrometers and spectroscopic instrumentation; Nanophotonics and photonic crystals; Fluorescence correlation spectroscopy; Fluorescence resonance energy transfer; Fluorescence spectroscopy; Imaging techniques; Optical components; Quantum key distribution | ||||
| Abstract | This document provides supplementary information to “Spectrally multiplexed single-photon detection with hybrid superconducting nanophotonic circuits", DOI:10.1364/optica.4.000557. Here we detail the on-chip spectrometer design, its characterization and the experimental setup we used. In addition, we present a detailed report concerning the characterization of the superconducting nanowire single photon detectors. In the final sections, we describe sample preparation and characterization of the nanodiamonds containing silicon vacancy color centers. | ||||
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| Publisher | Osa | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | Kahl:17 | Serial | 1218 | ||
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| Author | Neroev, V. V.; Iomdina, E. N.; Khandzhyan, A. T.; Khodzhabekyan, N. V.; Sengaeva, M. D.; Ivanova, A. V.; Seliverstov, S. V.; Teplyakova, K. O.; Goltsman, G. N. | ||||
| Title | Experimental study of the effect of corneal hydration and its biomechanical properties on the results of photorefractive keratectomy | Type | Journal Article | ||
| Year | 2021 | Publication | Vestn. Oftalmol. | Abbreviated Journal | Vestn. Oftalmol. |
| Volume | 137 | Issue | 3 | Pages | 68-75 |
| Keywords | THz scanning, cornea, photorefractive keratectomy, medicine | ||||
| Abstract | Water content in the cornea may affect the outcome of its excimer laser ablation, especially in presbyopic patients with myopic refraction. This hypothesis can be tested by scanning the cornea in the terahertz (THz) range to determine its hydration level. Purpose: To study the effect of hydration of the cornea determined by non-contact THz scanning and its biomechanical parameters on the results of photorefractive keratectomy (PRK) in an experiment. Material and methods: PRK was performed using the Nidek EC-5000 QUEST excimer laser on 8 rabbit eyes. Corneal hydration was evaluated by determining the reflection coefficient (RC) in the THz electromagnetic radiation range before PRK, after 3-5 days, and after 1, 2, 3, and 4 months. Clinical examination included autorefractometry, assessment of corneal thickness and other anatomical and optical parameters of the anterior eye segment (Galilei G6, Ziemer Ophthalmic Systems AG 6.0.2, Switzerland), measurement of corneal hysteresis (CH) and corneal resistance factor (CRF) using the Ocular Response Analyzer (ORA; Reichert, USA), as well as tear production (Schirmer test). Results: The initial water content in the cornea has a significant effect on the thickness of the removed layer, i.e. on the PRK effect, with correlation coefficient of Rs= -0.976 (p<0.01). The correlation between CH and the ablation depth is less pronounced (Rs=0.643), and CRF had no correlation with it (Rs= -0.089). Biomechanical indicators of the cornea depend on its hydration: changes in CH and CRF after excimer laser ablation qualitatively coincide with changes in RC, the correlation coefficient between RC and the initial value of CH is R= -0.619 (moderate negative correlation). Conclusion: THz scanning is an effective non-contact technology for monitoring corneal hydration level. The mismatch of the hypoeffect of keratorefractive excimer laser intervention planned for patients with presbyopia with the actual outcome can be caused by individual decrease in the initial water content in the cornea. |
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| Language | Russian | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | Serial | 1794 | |||
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| Author | Iomdina, E. N.; Seliverstov, S. V.; Sianosyan, A. A.; Teplyakova, K. O.; Rusova, A. A.; Goltsman, G. N. | ||||
| Title | Terahertz scanning for evaluation of corneal and scleral hydration | Type | Journal Article | ||
| Year | 2018 | Publication | Sovremennye tehnologii v medicine | Abbreviated Journal | STM |
| Volume | 10 | Issue | 4 | Pages | 143-149 |
| Keywords | BWO; Golay cell; medicine; cornea; sclera; THz radiation; corneal hydration; backward-wave oscillator; avalanche transit-time diode; IMPATT diode | ||||
| Abstract | The aim of the investigation was to study the prospects of using continuous THz scanning of the cornea and the sclera to determine water concentration in these tissues and on the basis of the obtained data to develop the experimental installation for monitoring corneal and scleral hydration degree.Materials and Methods. To evaluate corneal and scleral transmittance and reflectance spectra in the THz range, the developed experimental installations were used to study 3 rabbit corneas and 3 scleras, 2 whole rabbit eyes, and 3 human scleras. Besides, two rabbit eyes were studied in vivo prior to keratorefractive surgery as well as 10 and 21 days following the surgery (LASIK).Results. There have been created novel experimental installations enabling in vitro evaluation of frequency dependence of corneal and scleral transmittance coefficients and reflectance coefficients on water percentage in the THz range. Decrease in corneal water content by 1% was found to lead to reliably established decrease in the reflected signal by 13%. The reflectance spectrum of the whole rabbit eye was measured in the range of 0.13–0.32 THz. The study revealed the differences between the indices of rabbit cornea and sclera, as well as rabbit and human sclera. There was developed a laboratory model of the installation for in vivo evaluation of corneal and scleral hydration using THz radiation.Conclusion. The preliminary findings show that the proposed technique based on the use of continuous THz radiation can be employed to create a device for noninvasive control of corneal and scleral hydration. | ||||
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| Notes | Approved | no | |||
| Call Number | Serial | 1315 | |||
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