| 1. |
- Gordeeva, A. V., et al.
(författare)
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Observation of Photon Noise by a Parallel-Series Array of Cold-Electron Bolometers
- 2017
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Ingår i: 2017 16th International Superconductive Electronics Conference, ISEC 2017. ; 2018-January, s. 9-11
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Konferensbidrag (refereegranskat)abstract
- The quasioptical qualification of cold-electron bolometers (CEB) operated in the cross-slot antenna at 350GHz, are presented. The photon noise observation by a parallel/series array of CEBs is demonstrated for power loads of the order of 1 pW. The experimental results have been fitted to theoretical model with two heat-balance equations for the absorber and for superconducting electrodes. The measured noise has been decomposed into several terms with the help of theory. It is demonstrated that the photon noise exceeds any other noise components at some voltage range, that allows us to conclude that the bolometers see the photon noise. A shape of the noise dependence on the bolometer voltage originates from the photonic component according to the theory. In the additional experiment on heating of the sample holder the photonic component is almost absent and the total noise is lower, proving the presence of the photon noise in the first experiment.
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| 2. |
- Gordeeva, A. V., et al.
(författare)
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Observation of photon noise by cold-electron bolometers
- 2017
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 110:16
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Tidskriftsartikel (refereegranskat)abstract
- We have observed the photon noise by measuring a response to the black body 350 GHz radiation and noise of the cold-electron bolometers (CEBs). The experimental results have been fit to the theoretical model of CEBs with two heat-balance equations. The measured noise has been decomposed into several terms with the help of theory. It is demonstrated that the photon noise exceeds any other noise components, which allows us to conclude that the bolometers measure the photon noise. Moreover, a peculiar shape of the noise dependence on the absorbed power originates completely from the photonic component according to the theory. In the additional experiment on heating of the cryostat plate together with the sample holder, we have observed the near independence of the noise on the electron temperature of the absorber, which has provided another proof of the presence of the photon noise in the first experiment. The least ratio between internal and photon noise equivalent powers, observed in our experiments, is 1.1 for the absorbed power of 1-2 pW.
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| 3. |
- Kuzmin, Leonid, 1946, et al.
(författare)
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Photon-noise-limited cold-electron bolometer based on strong electron self-cooling for high-performance cosmology missions
- 2019
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Ingår i: Communications Physics. - : Springer Science and Business Media LLC. - 2399-3650. ; 2:1
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Tidskriftsartikel (refereegranskat)abstract
- Bolometers for balloon and space missions have seen extensive development because of their capacity to test primordial conditions of the Universe. The major improvements consist in lowering the operating temperature to reach higher sensitivities. Here we show that an array of 192 cold-electron bolometers (CEB) demonstrates photon-noise-limited operation at the cryostat temperature of 310 mK due to effective self-cooling of the absorber. The direct electron cooling of nanoabsorber placed between normal metal - insulator - superconductor junctions has considerably higher efficiency than indirect cooling through massive suspended platform, that requires overcoming a weak electron-phonon conductance. The electron temperature reached 120 mK without a power load, and 225 mK with a 60 pW power load with self-noise of a single bolometer below 3⋅10-18WHz-1∕2 at a 0.01 pW power load. This bolometer works at electron temperature less than phonon temperature, thus being a good candidate for future space missions without the use of dilution refrigerators.
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| 4. |
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| 5. |
- Kuzmin, Leonid, 1946, et al.
(författare)
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Realization of Cold-Electron Bolometers with Ultimate Sensitivity due to Strong Electron Self-Cooling
- 2017
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Ingår i: 2017 16TH INTERNATIONAL SUPERCONDUCTIVE ELECTRONICS CONFERENCE (ISEC). - 2374-4952. - 9781509058686 ; 2018-January
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Konferensbidrag (refereegranskat)abstract
- We have realized an ultimate photon-noise-limited array of cold-electron bolometers (CEBs) for OLIMPO Balloon Telescope. The CEB array demonstrates very effective electron self-cooling of the absorber from 310 mK to 100 mK without optical power load, P-0, and from 310 mK to 160 mK with P-0=20 pW at v=345 GHz. Due to this effective electron cooling acting as strong electrothermal feedback, the ultimate photon-noise-limited mode of operation is realized in the range of P-0 starting from 8 pW and up to P-0=20 pW at T-ph=330 mK. To our knowledge, there is no analog in the world for bolometers working at electron temperature less than phonon temperature.
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| 6. |
- Kuzmin, Leonid, 1946, et al.
(författare)
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Strong Electron Self-Cooling in the Cold-Electron Bolometers Designed for CMB Measurements
- 2018
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 969:1
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Konferensbidrag (refereegranskat)abstract
- We have realized cold-electron bolometers (CEB) with direct electron self-cooling of the nanoabsorber by SIN (Superconductor-Insulator-Normal metal) tunnel junctions. This electron self-cooling acts as a strong negative electrothermal feedback, improving noise and dynamic properties. Due to this cooling the photon-noise-limited operation of CEBs was realized in array of bolometers developed for the 345 GHz channel of the OLIMPO Balloon Telescope in the power range from 10 pW to 20 pW at phonon temperature T ph =310 mK. The negative electrothermal feedback in CEB is analogous to TES but instead of artificial heating we use cooling of the absorber. The high efficiency of the electron self-cooling to T e =100 mK without power load and to Te=160 mK under power load is achieved by:-a very small volume of the nanoabsorber (0.02 μm 3 ) and a large area of the SIN tunnel junctions,-effective removal of hot quasiparticles by arranging double stock at both sides of the junctions and close position of the normal metal traps,-self-protection of the 2D array of CEBs against interferences by dividing them between N series CEBs (for voltage interferences) and M parallel CEBs (for current interferences),-suppression of Andreev reflection by a thin layer of Fe in the AlFe absorber. As a result even under high power load the CEBs are working at electron temperature T e less than T ph . To our knowledge, there is no analogue in the bolometers technology in the world for bolometers working at electron temperature colder than phonon temperature.
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