| Records |
| Author |
Seliverstov, S. V.; Anfertyev, V. A.; Tretyakov, I. V.; Ozheredov, I. A.; Solyankin, P. M.; Revin, L. S.; Vaks, V. L.; Rusova, A. A.; Goltsman, G. N.; Shkurinov, A. P. |
| Title |
Terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser |
Type |
Journal Article |
Year  |
2017 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
60 |
Issue |
7 |
Pages |
518-524 |
| Keywords |
NbN HEB mixer, QCL |
| Abstract |
We study characteristics of the laboratory prototype of a terahertz heterodyne receiver with an electron-heating mixer and a heterodyne based on the quantum-cascade laser. The results obtained demonstrate the possibility to use this receiver as a basis for creation of a high-sensitivity terahertz spectrometer, which can be used in many basic and practical applications. A significant advantage of this receiver will be the possibility of placing the mixer and heterodyne in the same cryostat, which will reduce the device dimensions considerably. The obtained experimental results are analyzed, and methods of optimizing the parameters of the receiver are proposed. |
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0033-8443 |
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no |
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Serial |
1322 |
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| Author |
Elezov, M. S.; Ozhegov, R. V.; Goltsman, G. N.; Makarov, V.; Vinogradov, E. A.; Naumov, A. V.; Gladush, M. G.; Karimullin, K. R. |
| Title |
Development of the experimental setup for investigation of latching of superconducting single-photon detector caused by blinding attack on the quantum key distribution system |
Type |
Conference Article |
| Year |
2017 |
Publication |
EPJ Web Conf. |
Abbreviated Journal |
EPJ Web Conf. |
| Volume |
132 |
Issue |
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Pages |
01004 (1 to 2) |
| Keywords |
QKD, SSPD, SNSPD |
| Abstract |
Recently bright-light control of the SSPD has been demonstrated. This attack employed a “backdoor” in the detector biasing scheme. Under bright-light illumination, SSPD becomes resistive and remains “latched” in the resistive state even when the light is switched off. While the SSPD is latched, Eve can simulate SSPD single-photon response by sending strong light pulses, thus deceiving Bob. We developed the experimental setup for investigation of a dependence on latching threshold of SSPD on optical pulse length and peak power. By knowing latching threshold it is possible to understand essential requirements for development countermeasures against blinding attack on quantum key distribution system with SSPDs. |
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2100-014X |
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no |
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1327 |
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| Author |
Bandurin, D. A.; Svintsov, D.; Gayduchenko, I.; Xu, S. G.; Principi, A.; Moskotin, M.; Tretyakov, I.; Yagodkin, D.; Zhukov, S.; Taniguchi, T.; Watanabe, K.; Grigorieva, I. V.; Polini, M.; Goltsman, G. N.; Geim, A. K.; Fedorov, G. |
| Title |
Resonant terahertz detection using graphene plasmons |
Type |
Journal Article |
| Year |
2018 |
Publication |
Nat. Commun. |
Abbreviated Journal |
Nat. Commun. |
| Volume |
9 |
Issue |
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Pages |
5392 (1 to 8) |
| Keywords |
THz, graphene plasmons |
| Abstract |
Plasmons, collective oscillations of electron systems, can efficiently couple light and electric current, and thus can be used to create sub-wavelength photodetectors, radiation mixers, and on-chip spectrometers. Despite considerable effort, it has proven challenging to implement plasmonic devices operating at terahertz frequencies. The material capable to meet this challenge is graphene as it supports long-lived electrically tunable plasmons. Here we demonstrate plasmon-assisted resonant detection of terahertz radiation by antenna-coupled graphene transistors that act as both plasmonic Fabry-Perot cavities and rectifying elements. By varying the plasmon velocity using gate voltage, we tune our detectors between multiple resonant modes and exploit this functionality to measure plasmon wavelength and lifetime in bilayer graphene as well as to probe collective modes in its moire minibands. Our devices offer a convenient tool for further plasmonic research that is often exceedingly difficult under non-ambient conditions (e.g. cryogenic temperatures) and promise a viable route for various photonic applications. |
| Address |
Physics Department, Moscow State University of Education (MSPU), Moscow, Russian Federation, 119435. fedorov.ge@mipt.ru |
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2041-1723 |
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no |
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1148 |
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Elezov, M. S.; Scherbatenko, M. L.; Sych, D. V.; Goltsman, G. N. |
| Title |
Active and passive phase stabilization for the all-fiber Michelson interferometer |
Type |
Conference Article |
| Year |
2018 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1124 |
Issue |
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Pages |
051014 (1 to 5) |
| Keywords |
Michelson interferometer, phase stabilization |
| Abstract |
We put forward two methods for phase stabilization in the all-fiber Michelson interferometer. To perform passive phase stabilization, we use a heat bath for all fibers and electro-optical components, and put the interferometer in a hermetic case. To perform active phase stabilization, we monitor output power of the interferometer and develop an electronic feedback control. The phase stabilization methods enable stable interference pattern for several minutes, and can be helpful for the development of the optimal quantum receiver for coherent signals. |
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| ISSN |
1742-6588 |
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no |
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1299 |
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Baeva, E. M.; Sidorova, M. V.; Korneev, A. A.; Smirnov, K. V.; Divochy, A. V.; Morozov, P. V.; Zolotov, P. I.; Vakhtomin, Y. B.; Semenov, A. V.; Klapwijk, T. M.; Khrapai, V. S.; Goltsman, G. N. |
| Title |
Thermal properties of NbN single-photon detectors |
Type |
Journal Article |
| Year |
2018 |
Publication |
Phys. Rev. Applied |
Abbreviated Journal |
Phys. Rev. Applied |
| Volume |
10 |
Issue |
6 |
Pages |
064063 (1 to 8) |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We investigate thermal properties of a NbN single-photon detector capable of unit internal detection efficiency. Using an independent calibration of the coupling losses, we determine the absolute optical power absorbed by the NbN film and, via resistive superconductor thermometry, the temperature dependence of the thermal resistance Z(T) of the NbN film. In principle, this approach permits simultaneous measurement of the electron-phonon and phonon-escape contributions to the energy relaxation, which in our case is ambiguous because of the similar temperature dependencies. We analyze Z(T) with a two-temperature model and impose an upper bound on the ratio of electron and phonon heat capacities in NbN, which is surprisingly close to a recent theoretical lower bound for the same quantity in similar devices. |
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2331-7019 |
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no |
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Serial |
1226 |
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Nikoghosyan, A. S.; Martirosyan, R. M.; Hakhoumian, A. A.; Makaryan, A. H.; Tadevosyan, V. R.; Goltsman, G. N.; Antipov, S. V. |
| Title |
Effect of absorption on the efficiency of THz radiation generation in a nonlinear crystal placed into a waveguide |
Type |
Journal Article |
| Year |
2018 |
Publication |
Armenian J. Phys. |
Abbreviated Journal |
Armenian J. Phys. |
| Volume |
11 |
Issue |
4 |
Pages |
257-262 |
| Keywords |
THz, waveguide, nonlinear crystal |
| Abstract |
The effect of THz radiation absorption on the efficiency of generation of coherent THz radiation in a nonlinear optical crystal placed into a metal rectangular waveguide is studied. The efficiency of the nonlinear conversion of optical laser radiation to the THz band is also a function of the phase-matching (PM) condition inside the nonlinear crystal. The method of partial filling of a metal waveguide with a nonlinear optical crystal is used to ensure phase matching. Phase matching was obtained by the proper choice of the thickness of the nonlinear crystal, namely the degree of partial filling of the waveguide. We have studied the THz radiation attenuation caused by the losses in both the metal walls of the waveguide and in the crystal, taking into account the dimension of the cross section of the waveguide, the degree of partial filling and its dielectric constant. |
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| ISSN |
1829-1171 |
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no |
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Serial |
1291 |
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Matyushkin, Y. E.; Gayduchenko, I. A.; Moskotin, M. V.; Goltsman, G. N.; Fedorov, G. E.; Rybin, M. G.; Obraztsova, E. D. |
| Title |
Graphene-layer and graphene-nanoribbon FETs as THz detectors |
Type |
Conference Article |
| Year |
2018 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1124 |
Issue |
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Pages |
051054 |
| Keywords |
field-effect transistor, FET, monolayer graphene, graphene nanoribbons |
| Abstract |
We report on detection of sub-THz radiation (129-430 GHz) using graphene based asymmetric field-effect transistor (FET) structures with different channel geometry: monolayer graphene, graphene nanoribbons. In all devices types we observed the similar trends of response on sub-THz radiation. The response fell with increasing frequency at room temperature, but increased with increasing frequency at 77 K. Our calculations show that the change in the trend of the frequency dependence at 77 K is associated with the appearance of plasma waves in the graphene channel. Unusual properties of p-n junctions in graphene are highlighted using devices of special geometry. |
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1742-6588 |
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no |
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Serial |
1300 |
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Moskotin, M. V.; Gayduchenko, I. A.; Goltsman, G. N.; Titova, N.; Voronov, B. M.; Fedorov, G. F.; Pyatkov, F.; Hennrich, F. |
| Title |
Bolometric effect for detection of sub-THz radiation with devices based on carbon nanotubes |
Type |
Conference Article |
| Year |
2018 |
Publication |
J. Phys.: Conf. Ser. |
Abbreviated Journal |
J. Phys.: Conf. Ser. |
| Volume |
1124 |
Issue |
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Pages |
051050 (1 to 5) |
| Keywords |
field-effect transistor, FET, carbon nanotube, CNT |
| Abstract |
In this work we investigate the response on THz radiation of a FET device based on an individual carbon nanotube conductance channel. It was already shown, that the response of such devices can be either of diode rectification origin or of thermoelectric effect origin or of their combination. In this work we demonstrate that at 77K and 8K temperatures strong bolometric effect also makes a significant contribution to the response. |
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1742-6588 |
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no |
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1301 |
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Sidorova, M. V.; Kozorezov, A. G.; Semenov, A. V.; Korneeva, Y. P.; Mikhailov, M. Y.; Devizenko, A. Y.; Korneev, A. A.; Chulkova, G. M.; Goltsman, G. N. |
| Title |
Nonbolometric bottleneck in electron-phonon relaxation in ultrathin WSi films |
Type |
Journal Article |
| Year |
2018 |
Publication |
Phys. Rev. B |
Abbreviated Journal |
Phys. Rev. B |
| Volume |
97 |
Issue |
18 |
Pages |
184512 (1 to 13) |
| Keywords |
WSi films, diffusion constant, SSPD, SNSPD |
| Abstract |
We developed the model of the internal phonon bottleneck to describe the energy exchange between the acoustically soft ultrathin metal film and acoustically rigid substrate. Discriminating phonons in the film into two groups, escaping and nonescaping, we show that electrons and nonescaping phonons may form a unified subsystem, which is cooled down only due to interactions with escaping phonons, either due to direct phonon conversion or indirect sequential interaction with an electronic system. Using an amplitude-modulated absorption of the sub-THz radiation technique, we studied electron-phonon relaxation in ultrathin disordered films of tungsten silicide. We found an experimental proof of the internal phonon bottleneck. The experiment and simulation based on the proposed model agree well, resulting in τe−ph∼140–190 ps at TC=3.4K, supporting the results of earlier measurements by independent techniques. |
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2469-9950 |
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no |
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1305 |
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Tretyakov, I. V.; Anfertyev, V. A.; Revin, L. S.; Kaurova, N. S.; Voronov, B. M.; Vaks, V. L.; Goltsman, G. N. |
| Title |
Sensitivity and resolution of a heterodyne receiver based on the NbN HEB mixer with a quantum-cascade laser as a local oscillator |
Type |
Journal Article |
| Year |
2018 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
60 |
Issue |
12 |
Pages |
988-992 |
| Keywords |
NbN HEB mixer |
| Abstract |
We present the results of experimental studies of the basic characteristics and operation features of a terahertz heterodyne detector based on the superconducting NbN HEB mixer and a quantum cascade laser as a local oscillator operating at a frequency of 2.02 THz. The measured noise temperature of such a mixer amounted to 1500 K. The spectral resolution of the detector is determined by the width of the local-oscillator spectral line whose measured value does not exceed 1 MHz. The quantum-cascade laser could be linearly tuned with respect to frequency with the coefficient 7.2 MHz/mA within the limits of the current oscillation bandwidth. |
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0033-8443 |
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no |
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1307 |
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Gayduchenko, I. A.; Fedorov, G. E.; Moskotin, M. V.; Yagodkin, D. I.; Seliverstov, S. V.; Goltsman, G. N.; Yu Kuntsevich, A.; Rybin, M. G.; Obraztsova, E. D.; Leiman, V. G.; Shur, M. S.; Otsuji, T.; Ryzhii, V. I. |
| Title |
Manifestation of plasmonic response in the detection of sub-terahertz radiation by graphene-based devices |
Type |
Journal Article |
| Year |
2018 |
Publication |
Nanotechnol. |
Abbreviated Journal |
Nanotechnol. |
| Volume |
29 |
Issue |
24 |
Pages |
245204 (1 to 8) |
| Keywords |
single layer graphene, graphene nanoribbons |
| Abstract |
We report on the sub-terahertz (THz) (129-450 GHz) photoresponse of devices based on single layer graphene and graphene nanoribbons with asymmetric source and drain (vanadium and gold) contacts. Vanadium forms a barrier at the graphene interface, while gold forms an Ohmic contact. We find that at low temperatures (77 K) the detector responsivity rises with the increasing frequency of the incident sub-THz radiation. We interpret this result as a manifestation of a plasmonic effect in the devices with the relatively long plasmonic wavelengths. Graphene nanoribbon devices display a similar pattern, albeit with a lower responsivity. |
| Address |
Physics Department, Moscow State University of Education, Moscow 119991, Russia. National Research Center 'Kurchatov Institute', 123182, Moscow, Russia |
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0957-4484 |
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| Notes |
PMID:29553479 |
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no |
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1308 |
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Florya, I. N.; Korneeva, Y. P.; Mikhailov, M. Y.; Devizenko, A. Y.; Korneev, A. A.; Goltsman, G. N. |
| Title |
Photon counting statistics of superconducting single-photon detectors made of a three-layer WSi film |
Type |
Journal Article |
| Year |
2018 |
Publication |
Low Temp. Phys. |
Abbreviated Journal |
Low Temp. Phys. |
| Volume |
44 |
Issue |
3 |
Pages |
221-225 |
| Keywords |
WSi SSPD, SNSPD |
| Abstract |
Superconducting nanowire single-photon detectors (SNSPD) are used in quantum optics when record-breaking time resolution, high speed, and exceptionally low levels of dark counts (false readings) are required. Their detection efficiency is limited, however, by the absorption coefficient of the ultrathin superconducting film for the detected radiation. One possible way of increasing the detector absorption without limiting its broadband response is to make a detector in the form of several vertically stacked layers and connect them in parallel. For the first time we have studied single-photon detection in a multilayer structure consisting of three superconducting layers of amorphous tungsten silicide (WSi) separated by thin layers of amorphous silicon. Two operating modes of the detector are illustrated: an avalanche regime and an arm-trigger regime. A shift in these modes occurs at currents of ∼0.5–0.6 times the critical current of the detector.
This work was supported by technical task No. 88 for scientific research at the National Research University “Higher School of Economics,” Grant No. 14.V25.31.0007 from the Ministry of Education and Science of Russia, and the work of G. N. Goltsman was supported by task No. 3.7328.2017/VU of the Ministry of Education and Science of Russia. |
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1063-777X |
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no |
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1310 |
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Korneeva, Y. P.; Vodolazov, D. Y.; Semenov, A. V.; Florya, I. N.; Simonov, N.; Baeva, E.; Korneev, A. A.; Goltsman, G. N.; Klapwijk, T. M. |
| Title |
Optical single photon detection in micron-scaled NbN bridges |
Type |
Miscellaneous |
| Year |
2018 |
Publication |
arXiv |
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Issue |
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Pages |
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| Keywords |
SSPD |
| Abstract |
We demonstrate experimentally that single photon detection can be achieved in micron-wide NbN bridges, with widths ranging from 0.53 μm to 5.15 μm and for photon-wavelengths from 408 nm to 1550 nm. The microbridges are biased with a dc current close to the experimental critical current, which is estimated to be about 50 % of the theoretically expected depairing current. These results offer an alternative to the standard superconducting single-photon detectors (SSPDs), based on nanometer scale nanowires implemented in a long meandering structure. The results are consistent with improved theoretical modelling based on the theory of non-equilibrium superconductivity including the vortex-assisted mechanism of initial dissipation. |
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Duplicated as 1303 |
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no |
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1312 |
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Tretyakov, Ivan; Kaurova, N.; Voronov, B. M.; Goltsman, G. N. |
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About effect of the temperature operating conditions on the noise temperature and noise bandwidth of the terahertz range NbN hot-electron bolometers |
Type |
Abstract |
| Year |
2018 |
Publication |
Proc. 29th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 29th Int. Symp. Space Terahertz Technol. |
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Issue |
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Pages |
113 |
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NbN HEB mixer |
| Abstract |
Results of an experimental study of the noise temperature (Tn) and noise bandwidth (NBW) of the superconductor NbN hot-electron bolometer (HEB) mixer as a function of its temperature (Tb) and NbN bridge length are presented. It was determined that the NBW of the mixer is significantly wider at temperatures close to the critical ones (Tc) than are values measured at 4.2 K. The NBW of the mixer measured at the heterodyne frequency of 2.5 THz at temperature Tb close to Tc was ~13 GHz, as compared with 6 GHz at Tb = 4.2 K. This experiment clearly demonstrates the limitation of the thermal flow from the NbN bridge at Tb ≪ Tc for mixers manufactured by the in situ technique. This limitation is close in its nature to the Andreev reflection on the superconductor/metal boundary. In this case, the noise temperature of the studied mixer increased from 1100 to 3800 K. |
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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 |
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Journal Article |
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2018 |
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Sovremennye tehnologii v medicine |
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STM |
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10 |
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4 |
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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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1315 |
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