| Records |
| Author |
Pentin, I.; Vakhtomin, Y.; Seleznev, V.; Smirnov, K. |
| Title |
Hot electron energy relaxation time in vanadium nitride superconducting film structures under THz and IR radiation |
Type |
Journal Article |
| Year |
2020 |
Publication |
Sci. Rep. |
Abbreviated Journal |
Sci. Rep. |
| Volume |
10 |
Issue |
1 |
Pages |
16819 |
| Keywords |
VN HEB |
| Abstract |
The paper presents the experimental results of studying the dynamics of electron energy relaxation in structures made of thin (d approximately 6 nm) disordered superconducting vanadium nitride (VN) films converted to a resistive state by high-frequency radiation and transport current. Under conditions of quasi-equilibrium superconductivity and temperature range close to critical (~ Tc), a direct measurement of the energy relaxation time of electrons by the beats method arising from two monochromatic sources with close frequencies radiation in sub-THz region (omega approximately 0.140 THz) and sources in the IR region (omega approximately 193 THz) was conducted. The measured time of energy relaxation of electrons in the studied VN structures upon heating of THz and IR radiation completely coincided and amounted to (2.6-2.7) ns. The studied response of VN structures to IR (omega approximately 193 THz) picosecond laser pulses also allowed us to estimate the energy relaxation time in VN structures, which was ~ 2.8 ns and is in good agreement with the result obtained by the mixing method. Also, we present the experimentally measured volt-watt responsivity (S~) within the frequency range omega approximately (0.3-6) THz VN HEB detector. The estimated values of noise equivalent power (NEP) for VN HEB and its minimum energy level (deltaE) reached NEP@1MHz approximately 6.3 x 10(-14) W/ radicalHz and deltaE approximately 8.1 x 10(-18) J, respectively. |
| Address |
National Research University Higher School of Economics, 20 Myasnitskaya Str., Moscow, 101000, Russia |
| 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 |
2045-2322 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:33033360; PMCID:PMC7546726 |
Approved |
no |
| Call Number |
|
Serial |
1797 |
| Permanent link to this record |
| |
|
| |
| Author |
Gorokhov, G.; Bychanok, D.; Gayduchenko, I.; Rogov, Y.; Zhukova, E.; Zhukov, S.; Kadyrov, L.; Fedorov, G.; Ivanov, E.; Kotsilkova, R.; Macutkevic, J.; Kuzhir, P. |
| Title |
THz spectroscopy as a versatile tool for filler distribution diagnostics in polymer nanocomposites |
Type |
Journal Article |
| Year |
2020 |
Publication |
Polymers (Basel) |
Abbreviated Journal |
Polymers (Basel) |
| Volume |
12 |
Issue |
12 |
Pages |
3037 (1 to 14) |
| Keywords |
THz spectroscopy; nanocomposites, percolation threshold, time-domain spectroscopy, time-domain spectrometer, TDS |
| Abstract |
Polymer composites containing nanocarbon fillers are under intensive investigation worldwide due to their remarkable electromagnetic properties distinguished not only by components as such, but the distribution and interaction of the fillers inside the polymer matrix. The theory herein reveals that a particular effect connected with the homogeneity of a composite manifests itself in the terahertz range. Transmission time-domain terahertz spectroscopy was applied to the investigation of nanocomposites obtained by co-extrusion of PLA polymer with additions of graphene nanoplatelets and multi-walled carbon nanotubes. The THz peak of permittivity's imaginary part predicted by the applied model was experimentally shown for GNP-containing composites both below and above the percolation threshold. The physical nature of the peak was explained by the impact on filler particles excluded from the percolation network due to the peculiarities of filler distribution. Terahertz spectroscopy as a versatile instrument of filler distribution diagnostics is discussed. |
| Address |
Institute of Photonics, University of Eastern Finland, Yliopistokatu 7, FI-80101 Joensuu, Finland |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2073-4360 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:33353036; PMCID:PMC7767186 |
Approved |
no |
| Call Number |
|
Serial |
1780 |
| Permanent link to this record |
| |
|
| |
| Author |
Gayduchenko, I.; Xu, S. G.; Alymov, G.; Moskotin, M.; Tretyakov, I.; Taniguchi, T.; Watanabe, K.; Goltsman, G.; Geim, A. K.; Fedorov, G.; Svintsov, D.; Bandurin, D. A. |
| Title |
Tunnel field-effect transistors for sensitive terahertz detection |
Type |
Journal Article |
| Year |
2021 |
Publication |
Nat. Commun. |
Abbreviated Journal |
Nat. Commun. |
| Volume |
12 |
Issue |
1 |
Pages |
543 |
| Keywords |
field-effect transistors, bilayer graphene, BLG |
| Abstract |
The rectification of electromagnetic waves to direct currents is a crucial process for energy harvesting, beyond-5G wireless communications, ultra-fast science, and observational astronomy. As the radiation frequency is raised to the sub-terahertz (THz) domain, ac-to-dc conversion by conventional electronics becomes challenging and requires alternative rectification protocols. Here, we address this challenge by tunnel field-effect transistors made of bilayer graphene (BLG). Taking advantage of BLG's electrically tunable band structure, we create a lateral tunnel junction and couple it to an antenna exposed to THz radiation. The incoming radiation is then down-converted by the tunnel junction nonlinearity, resulting in high responsivity (>4 kV/W) and low-noise (0.2 pW/[Formula: see text]) detection. We demonstrate how switching from intraband Ohmic to interband tunneling regime can raise detectors' responsivity by few orders of magnitude, in agreement with the developed theory. Our work demonstrates a potential application of tunnel transistors for THz detection and reveals BLG as a promising platform therefor. |
| Address |
Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA. bandurin@mit.edu |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2041-1723 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:33483488; PMCID:PMC7822863 |
Approved |
no |
| Call Number |
|
Serial |
1261 |
| Permanent link to this record |
| |
|
| |
| Author |
Morozov, P.; Lukina, M.; Shirmanova, M.; Divochiy, A.; Dudenkova, V.; Gol'tsman, G. N.; Becker, W.; Shcheslavskiy, V. I. |
| Title |
Singlet oxygen phosphorescence imaging by superconducting single-photon detector and time-correlated single-photon counting |
Type |
Journal Article |
| Year |
2021 |
Publication |
Opt. Lett. |
Abbreviated Journal |
Opt. Lett. |
| Volume |
46 |
Issue |
6 |
Pages |
1217-1220 |
| Keywords |
SSPD, SNSPD, applications |
| Abstract |
This Letter presents, to the best of our knowledge, a novel optical configuration for direct time-resolved measurements of luminescence from singlet oxygen, both in solutions and from cultured cells on photodynamic therapy. The system is based on the superconducting single-photon detector, coupled to the confocal scanner that is modified for the near-infrared measurements. The recording of a phosphorescence signal from singlet oxygen at 1270 nm has been done using time-correlated single-photon counting. The performance of the system is verified by measuring phosphorescence from singlet oxygen generated by the photosensitizers commonly used in photodynamic therapy: methylene blue and chlorin e6. The described system can be easily upgraded to the configuration when both phosphorescence from singlet oxygen and fluorescence from the cells can be detected in the imaging mode. Thus, co-localization of the signal from singlet oxygen with the areas inside the cells can be done. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0146-9592 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:33720151 |
Approved |
no |
| Call Number |
|
Serial |
1221 |
| Permanent link to this record |
| |
|
| |
| Author |
Iomdina, E. N.; Seliverstov, S. V.; Teplyakova, K. O.; Jani, E. V.; Pozdniakova, V. V.; Polyakova, O. N.; Goltsman, G. N. |
| Title |
Terahertz scanning of the rabbit cornea with experimental UVB-induced damage: in vivo assessment of hydration and its verification |
Type |
Journal Article |
| Year |
2021 |
Publication |
J. Biomed. Opt. |
Abbreviated Journal |
J. Biomed. Opt. |
| Volume |
26 |
Issue |
4 |
Pages |
|
| Keywords |
medicine; scheimpflug imaging; UVB; confocal microscopy; cornea; optical coherent tomography; rabbit eyes; terahertz radiation |
| Abstract |
SIGNIFICANCE: Water content plays a vital role in the normally functioning visual system; even a minor disruption in the water balance may be harmful. Today, no direct method exists for corneal hydration assessment, while it could be instrumental in early diagnosis and control of a variety of eye diseases. The use of terahertz (THz) radiation, which is highly sensitive to water content, appears to be very promising. AIM: To find out how THz scanning parameters of corneal tissue measured by an experimental setup, specially developed for in vivo contactless estimations of corneal reflectivity coefficient (RC), are related to pathological changes in the cornea caused by B-band ultraviolet (UVB) exposure. APPROACH: The setup was tested on rabbit eyes in vivo. Prior to the course of UVB irradiation and 1, 5, and 30 days after it, a series of examinations of the corneal state was made. At the same time points, corneal hydration was assessed by measuring RC. RESULTS: The obtained data confirmed the negative impact of UVB irradiation course on the intensity of tear production and on the corneal thickness and optical parameters. A significant (1.8 times) increase in RC on the 5th day after the irradiation course, followed by a slight decrease on the 30th day after it was revealed. The RC increase measured 5 days after the UVB irradiation course generally corresponded to the increase (by a factor of 1.3) of tear production. RC increase occurred with the corneal edema, which was manifested by corneal thickening (by 18.2% in the middle area and 17.6% in corneal periphery) and an increased volume of corneal tissue (by 17.6%). CONCLUSIONS: Our results demonstrate that the proposed approach can be used for in vivo contactless estimation of the reflectivity of rabbit cornea in the THz range and, thereby, of cornea hydration. |
| Address |
National Research University Higher School of Economics, Moscow Institute of Electronics and Mathema, Russia |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1083-3668 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:33834684; PMCID:PMC8027227 |
Approved |
no |
| Call Number |
|
Serial |
1258 |
| Permanent link to this record |
| |
|
| |
| Author |
Verevkin, A. A.; Ptitsina, N. G.; Chulcova, G. M.; Gol'Tsman, G. N.; Gershenzon, E. M.; Yngvesson, K. S. |
| Title |
Determination of the limiting mobility of a two-dimensional electron gas in AlxGa1-xAs/GaAs heterostructures and direct measurement of the energy relaxation time |
Type |
Journal Article |
| Year |
1996 |
Publication |
Phys. Rev. B Condens. Matter. |
Abbreviated Journal |
Phys. Rev. B Condens. Matter. |
| Volume |
53 |
Issue |
12 |
Pages |
R7592-R7595 |
| Keywords |
2DEG, AlGaAs/GaAs heterostructures |
| Abstract |
We present results for a method to measure directly the energy relaxation time (τe) for electrons in a single AlxGa1−xAs/GaAs heterojunction; measurements were performed from 1.6 to 15 K under quasiequilibrium conditions. We find τeαT−1 below 4 K, and τe independent of T above 4 K. We have also measured the energy-loss rate, ⟨Q⟩, by the Shubnikov-de Haas technique, and find ⟨Q⟩α(T3e−T3) for T<~4.2 K; Te is the electron temperature. The values and temperature dependence of τe and ⟨Q⟩ for T<4 K agree with calculations based on piezoelectric and deformation potential acoustic phonon scattering. At 4.2 K, we can also estimate the momentum relaxation time, τm, from our measured τe. This leads to a preliminary estimate of the phonon-limited mobility at 4.2 K of μ=3×107 cm2/Vs (ns=4.2×1011 cm−2), which agrees well with published numerical calculations, as well as with an earlier indirect estimate based on measurements on a sample with much higher mobility. |
| 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 |
0163-1829 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:9982274 |
Approved |
no |
| Call Number |
|
Serial |
1612 |
| Permanent link to this record |
| |
|
| |
| Author |
Finkel, M. I.; Maslennikov, S. N.; Gol'tsman, G. N. |
| Title |
Terahertz heterodyne receivers based on superconductive hot-electron bolometer mixers |
Type |
Journal Article |
| Year |
2005 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
48 |
Issue |
10-11 |
Pages |
859-864 |
| Keywords |
HEB, applications |
| Abstract |
We consider recent results in development of hot-electron bolometer mixers. Special attention is paid to optimization of the contacts between the antenna and the active area of a superconducting film. An important result in the study of the parasitic effect of direct detection is obtained during the measurement of the noise temperatures by the hot/cold load method. The latest results of studies of the waveguide hot-electron bolometer mixers and their successful practical applications are considered. Progress in development of high-frequency (over 1.3 THz) heterodyne receivers for several important international projects is discussed and new submillimeter radio astronomy projects ESPRIT and SAFIR are described. |
| 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 |
0033-8443 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
381 |
| Permanent link to this record |
| |
|
| |
| Author |
Finkel, M. I.; Maslennikov, S. N.; Gol'tsman, G. N. |
| Title |
The concept of the receiving complex for the “Millimetron” space radio telescope |
Type |
Journal Article |
| Year |
2007 |
Publication |
Radiophys. Quant. Electron. |
Abbreviated Journal |
Radiophys. Quant. Electron. |
| Volume |
50 |
Issue |
10-11 |
Pages |
837-846 |
| Keywords |
HEB, applications, Millimetron, VLBI |
| Abstract |
We consider the current status of research in the development of a submillimeter and far-infrared receiving instrument and propose promising solutions for the receivers of the spaceborne telescope “Millimetron,” which allow one to realize comprehensively the opportunities given by this international project administrated by the Astrospace Center of the P. N. Lebedev Physical Institute of the Russian Academy of Sciences. |
| 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 |
0033-8443 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
411 |
| Permanent link to this record |
| |
|
| |
| 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. |
| 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 |
|
Serial |
1315 |
| Permanent link to this record |
| |
|
| |
| Author |
Słysz, W.; Wegrzecki, M.; Bar, J.; Grabiec, P.; Górska, M.; Zwiller, V.; Latta, C.; Böhi, P.; Pearlman, A.J.; Cross, A.S.; Pan, D.; Kitaygorsky, J.; Komissarov, I.; Verevkin, A.; Milostnaya, I.; Korneev, A.; Minayeva, O.; Chulkova, G.; Smirnov, K.; Voronov, B.; Gol’tsman, G.N.; Sobolewski, R. |
| Title |
Fibre-coupled, single photon detector based on NbN superconducting nanostructures for quantum communications |
Type |
Journal Article |
| Year |
2007 |
Publication |
J. Modern Opt. |
Abbreviated Journal |
J. Modern Opt. |
| Volume |
54 |
Issue |
2-3 |
Pages |
315-326 |
| Keywords |
NbN SSPD, SNSPD |
| Abstract |
We present a novel, two-channel, single photon receiver based on two fibre-coupled, NbN, superconducting, single photon detectors (SSPDs). The SSPDs are nanostructured superconducting meanders and are known for ultrafast and efficient detection of visible-to-infrared photons. Coupling between the NbN detector and optical fibre was achieved using a micromechanical photoresist ring placed directly over the SSPD, holding the fibre in place. With this arrangement, we obtained coupling efficiencies up to ∼30%. Our experimental results showed that the best receiver had a near-infrared system quantum efficiency of 0.33% at 4.2 K. The quantum efficiency increased exponentially with the photon energy increase, reaching a few percent level for visible-light photons. The photoresponse pulses of our devices were limited by the meander high kinetic inductance and had the rise and fall times of approximately 250 ps and 5 ns, respectively. The receiver's timing jitter was in the 37 to 58 ps range, approximately 2 to 3 times larger than in our older free-space-coupled SSPDs. We stipulate that this timing jitter is in part due to optical fibre properties. Besides quantum communications, the two-detector arrangement should also find applications in quantum correlation experiments. |
| 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 |
0950-0340 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
|
Serial |
1434 |
| Permanent link to this record |
