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Author | Tong, C.-Y. Edward; Meledin, Denis; Blundell, Raymond; Erickson, Neal; Kawamura, Jonathan; Mehdi, Imran; Gol'tsman, Gregory | ||||
Title | A 1.5 THz hot-electron bolometer mixer operated by a planar diode-based local oscillator | Type | Abstract | ||
Year | 2003 | Publication | Proc. 14th Int. Symp. Space Terahertz Technol. | Abbreviated Journal | Proc. 14th Int. Symp. Space Terahertz Technol. |
Volume | Issue | Pages | 286 | ||
Keywords | waveguide NbN HEB mixers | ||||
Abstract ![]() |
We describe a 1.5 THz heterodyne receiver based on a superconductin g hot-electron bolometer mixer, which is pumped by an all-solid-state local oscillator chain. The bolometer is fabricated from a 3.5 nm-thick niobium nitride film deposited on a quartz substrate with a 200 nm-thick magnesium oxide buffer layer. The bolometer measures 0.15 fun in width and 1.5 1..tm in length. The chip consisting of the bolometer and mixer circuitry is incorporated in a fixed-tuned waveguide mixer block with a corru g ated feed horn. The local oscillator unit comprises of a cascade of four planar doublers followin g a MMIC-based W-band power amplifier. The local oscillator is coupled to the mixer using a Martin-Puplett interferometer. The local oscillator output power needed for optimal receiver performance is approximately 1 to 2 11W, and the chain is able to provide this power at a number of frequency points between 1.45 and 1.56 THz. By terminating the rf input with room temperature and 77 K loads, a Y-factor of 1.11 (DSB) has been measured at a local oscillator frequency of 1.476 THz at 3 GHz intermediate frequency. | ||||
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Notes | Approved | no | |||
Call Number | Serial | 1501 | |||
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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 | ||||
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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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Language | Russian | Summary Language | Original Title | ||
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Notes | 7 pages | Approved | no | ||
Call Number | Serial | 1824 | |||
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Author | Khosropanah P.; Baryshev A.; Zhang W.; Jellema W.; Hovenier J.N.; Gao G.R.; Klapwijk T.M; Paveliev D.G.; Williams B.S.; Kumar S.; Hu Q.; Reno J.L.; Klein B.; Hesler J.L. | ||||
Title | Phase-locking of a 2.7-THz quantum cascade laser to a microwave reference | Type | Journal Article | ||
Year | 2009 | Publication | Optics Letters | Abbreviated Journal | |
Volume | 34 | Issue | Pages | 2958-2960 | |
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We demonstrate the phase locking of a 2.7 THz metal–metal waveguide quantum cascade laser (QCL) to an external microwave signal. The reference is the 15th harmonic, generated by a semiconductor superlattice nonlinear device, of a signal at 182 GHz, which itself is generated by a multiplier chain (X12) from a microwave synthesizer at ~ 15 GHz. Both laser and reference radiations are coupled into a bolometer mixer, resulting in a beat signal, which is fed into a phase-lock loop. The spectral analysis of the beat signal con-firms that the QCL is phase locked. This result opens the possibility to extend heterodyne interferometers into the far-infrared range. |
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Notes | Approved | no | |||
Call Number | RPLAB @ atomics90 @ | Serial | 966 | ||
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Author | Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Klapwijk, T. M.; de Korte, P. A. J.; Voronov, B.; Gol'tsman, G. | ||||
Title | Doubling of sensitivity and bandwidth in phonon cooled hot electron bolometer mixers | Type | Journal Article | ||
Year | 2004 | Publication | Appl. Phys. Lett. | Abbreviated Journal | Appl. Phys. Lett. |
Volume | 84 | Issue | 11 | Pages | 1958-1960 |
Keywords | NbN HEB mixers | ||||
Abstract ![]() |
We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. We show experimentally that both the receiver noise temperature and the gain bandwidth can be improved by more than a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature TN,DSB=950 K at 2.5 THz and 4.3 K, uncorrected for losses in the optics. At the same bias point, we obtain an IF gain bandwidth of 6 GHz. |
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Notes | Approved | no | |||
Call Number | Serial | 352 | |||
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Author | Baselmans, J. J. A.; Hajenius, M.; Gao, J. R.; Baryshev, A.; Kooi, J.; Klapwijk, T. M.; Voronov, B.; de Korte, P.; Gol'tsman, G. | ||||
Title | NbN hot electron bolometer mixers: sensitivity, LO power, direct detection and stability | Type | Journal Article | ||
Year | 2005 | Publication | IEEE Trans. Appl. Supercond. | Abbreviated Journal | IEEE Trans. Appl. Supercond. |
Volume | 15 | Issue | 2 | Pages | 484-489 |
Keywords | HEB mixers, direct detection effect, stability, Allan variance | ||||
Abstract ![]() |
We demonstrate that the performance of NbN lattice cooled hot electron bolometer mixers depends strongly on the interface quality between the bolometer and the contact structure. Both the receiver noise temperature and the gain bandwidth can be improved by a factor of 2 by cleaning the interface and adding an additional superconducting interlayer to the contact pad. Using this we obtain a double sideband receiver noise temperature of 950 K at 2.5 THz and 4.3 K, using a 0.4/spl times/4 /spl mu/m HEB mixer with a spiral antenna. At the same bias point, we obtain an IF gain bandwidth of 6 GHz. To comply with current demands on THz mixers for use in space based receivers we reduce the device size to 0.15/spl times/1 /spl mu/m and use a twin slot antenna. We report measurements of the noise temperature, LO power requirement, stability and the direct detection effect, using a mixer with a 1.6 THz twin slot antenna and a 1.462 THz solid state LO source with calibrated output power. | ||||
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ISSN | 1051-8223 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | Serial | 546 | |||
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