Ozhegov RV, Smirnov AV, Vakhtomin YB, Smirnov KV, Divochiy AV, Goltsman GN. Ultrafast superconducting bolometer receivers for terahertz applications [abstract]. In: Proc. PIERS. 777 Concord Avenue, Suite 207 Cambridge, MA 02138: The Electromagnetics Academy; 2009. 867.
Abstract: The research by the group of Moscow State Pedagogical University into the hot-electron phenomena in thin superconducting films has led to the development of new types of detectors and their use both in fundamental and applied studies. In this paper, we present the results of testing the terahertz HEB receiver systems based on ultrathin (∼ 4 nm) NbN and MoRe detectors with a response time of 50 ps and 1 ns, respectively. We have developed three types of devices which differ in the way a terahertz signal is coupled to the detector and cover the following ranges: 0.3–3 THz, 0.1–30 THz and 25–70 THz. In the case of the receiving system optimized for 0.3–3 THz, the sensitive element (a strip of asuperconductor with planar dimensions of 0.2μm (length) by 1.7μm (width)) was integrated witha planar broadband log-spiral antenna. For additional focusing ofthe incident radiation a silicon hyperhemispherical lens was used. For the 0.1–30 THz receivingsystem, the sensitive element was patterned as parallel strips(2μm wide each) filling an area of 500×500μm2with a filling factor of 0.5. In the receivingsystem of this type we used direct coupling of the incident radiation to the sensitive element. Inthe 25–70 THz range (detector type 2/2a in Table 1) we used a square-shaped superconductingdetector with planar dimensions of 10×10μm2. Incident radiation was coupled to the detectorwith the use of a germanium hyperhemispherical lens.The response time of the above receiving systems is determined by the cooling rate of the hotelectrons in the film. That depends on the electron-phonon interaction time, which is less forultrathin NbN than in MoRe.
|
Finkel MI, Maslennikov SN, Gol'tsman GN. Terahertz heterodyne receivers based on superconductive hot-electron bolometer mixers. Radiophys Quant Electron. 2005;48(10-11):859–64.
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.
|
|
Karasik BS, Elantiev AI. Noise temperature limit of a superconducting hot-electron bolometer mixer. Appl Phys Lett. 1996;68(6):853–5.
|
Rönnung F, Cherednichenko S, Winkler D, Gol'tsman GN. A nanoscale YBCO mixer optically coupled with a bow tie antenna. Supercond Sci Technol. 1999;12(11):853–5.
Abstract: The bolometric response of YBa2Cu3O7-δ(YBCO) hot-electron bolometers (HEBs) to near-infrared radiation was studied. Devices were fabricated from a 50 nm thick film and had in-plane areas of 10 × 10 µm2, 2 × 0.2 µm2, 1 × 0.2µm2 and 0.5 × 0.2 µm2. We found that nonequilibrium phonons cool down more effectively for the bolometers with smaller area. For the smallest bolometer the bolometric component in the response is 10 dB less than for the largest one.
|
Finkel MI, Maslennikov SN, Gol'tsman GN. The concept of the receiving complex for the “Millimetron” space radio telescope. Radiophys Quant Electron. 2007;50(10-11):837–46.
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.
|
