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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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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1794 | |||
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| Author | Semenov, A. V.; Devyatov, I. A.; Korneev, A. A.; Smirnov, K. V.; Goltsman, G. N.; Melnikov, A. P. | ||||
| Title | Derivation of expression for thermodynamic potential of “dirty” superconductor | Type | Journal Article | ||
| Year | 2012 | Publication | Rus. J. Radio Electron. | Abbreviated Journal | Rus. J. Radio Electron. |
| Volume | Issue | 4 | Pages | ||
| Keywords | dirty superconductor, Usadel theory, thermodynamic potential | ||||
| Abstract | We derive a formula for thermodynamic potential of dirty superconductor which express it via isotropic quasiclassical Green functions of Usadel theory. Our result allows unify description of dynamic processes and fluctuations in superconducting nano-electronic devices. | ||||
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| Corporate Author | Thesis | ||||
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| Language | Russian | Summary Language | Original Title | ||
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| Area | Expedition | Conference | |||
| Notes | 7 pages | Approved | no | ||
| Call Number | Serial | 1824 | |||
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| Author | Gershenzon, E. M.; Goltsman, G. N.; Orlov, L. | ||||
| Title | Investigation of population and ionization of donor excited states in Ge | Type | Conference Article | ||
| Year | 1976 | Publication | Physics of Semiconductors | Abbreviated Journal | Physics of Semiconductors |
| Volume | Issue | Pages | 631-634 | ||
| Keywords | Ge, donor excited states | ||||
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| Address |
Amsterdam | ||||
| Corporate Author | Thesis | ||||
| Publisher | North-Holland Publishing Co. | Place of Publication | Editor | ||
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| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | Serial | 1732 | |||
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| Author | Averkin, A. S.; Shishkin, A. G.; Chichkov, V. I.; Voronov, B. M.; Goltsman, G. N.; Karpov, A.; Ustinov, A. V. | ||||
| Title | Tunable frequency-selective surface based on superconducting split-ring resonators | Type | Conference Article | ||
| Year | 2014 | Publication | 8th Metamaterials | Abbreviated Journal | 8th Metamaterials |
| Volume | Issue | Pages | |||
| Keywords | superconducting split-ring resonators | ||||
| Abstract | We study a possibility to use the 2D superconducting metamaterial as a tunable frequency-selective surface (FSS). The proposed FSS is made of sub-wavelength size (l/14) metamaterial unit cells, where a split-ring resonator is embedded in a small iris aperture in a metal plane. The split-ring resonator is made of NbN film, and its resonance frequency is tuned by the temperature of the sample, changing the kinetic inductance of NbN film. The Ansoft HFSS simulation predicts the FSS tuning range of about 10-20 %. The developed superconducting FSS may be used as a tunable band-pass filter or modulator. | ||||
| Address |
Copenhagen, Denmark | ||||
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| Area | Expedition | Conference | 8th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics – Metamaterials | ||
| Notes | Approved | no | |||
| Call Number | Serial | 1749 | |||
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| Author | Pernice, W. H. P.; Schuck, C.; Minaeva, O.; Li, M.; Goltsman, G. N.; Sergienko, A. V.; Tang, H. X. | ||||
| Title | High-speed and high-efficiency travelling wave single-photon detectors embedded in nanophotonic circuits | Type | Journal Article | ||
| Year | 2012 | Publication | Nat. Commun. | Abbreviated Journal | Nat. Commun. |
| Volume | 3 | Issue | Pages | 1325 (1 to 10) | |
| Keywords | waveguide SSPD | ||||
| Abstract | Ultrafast, high-efficiency single-photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. However, imperfect modal matching and finite photon absorption rates have usually limited their maximum attainable detection efficiency. Here we demonstrate superconducting nanowire detectors atop nanophotonic waveguides, which enable a drastic increase of the absorption length for incoming photons. This allows us to achieve high on-chip single-photon detection efficiency up to 91% at telecom wavelengths, repeatable across several fabricated chips. We also observe remarkably low dark count rates without significant compromise of the on-chip detection efficiency. The detectors are fully embedded in scalable silicon photonic circuits and provide ultrashort timing jitter of 18 ps. Exploiting this high temporal resolution, we demonstrate ballistic photon transport in silicon ring resonators. Our direct implementation of a high-performance single-photon detector on chip overcomes a major barrier in integrated quantum photonics. | ||||
| Address |
Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:23271658; PMCID:PMC3535416 | Approved | no | ||
| Call Number | Serial | 1375 | |||
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