|
Records |
Links |
|
Author |
Kawamura, J.; Hunter, T. R.; Tong, C. Y. E.; Blundell, R.; Papa, D. C.; Patt, F.; Peters, W.; Wilson, T.; Henkel, C.; Goltsman, G.; Gershenzon, E. |
|
|
Title |
Ground-based terahertz CO spectroscopy towards Orion |
Type |
Journal Article |
|
Year |
2002 |
Publication |
A&A |
Abbreviated Journal |
A&A |
|
|
Volume |
394 |
Issue |
1 |
Pages |
271-274 |
|
|
Keywords |
HEB mixers, applications |
|
|
Abstract |
Using a superconductive hot-electron bolometer heterodyne receiver on the 10-m Heinrich Hertz Telescope on Mount Graham, Arizona, we have obtained velocity-resolved 1.037 THz CO () spectra toward several positions along the Orion Molecular Cloud (OMC-1) ridge. We confirm the general results of prior observations of high-J CO lines that show that the high temperature, , high density molecular gas, , is quite extended, found along a ~ region centered on BN/KL. However, our observations have significantly improved angular resolution, and with a beam size of we are able to spatially and kinematically discriminate the emission originating in the extended quiescent ridge from the very strong and broadened emission originating in the compact molecular outflow. The ridge emission very close to the BN/KL region appears to originate from two distinct clouds along the line of sight with and ≈ . The former component dominates the emission to the south of BN/KL and the latter to the north, with a turnover point coincident with or near BN/KL. Our evidence precludes a simple rotation of the inner ridge and lends support to a model in which there are multiple molecular clouds along the line of sight towards the Orion ridge. |
|
|
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 |
322 |
|
Permanent link to this record |
|
|
|
|
Author |
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 |
|
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. |
|
|
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 |
1742-6588 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
|
Approved |
no |
|
|
Call Number |
|
Serial |
1300 |
|
Permanent link to this record |
|
|
|
|
Author |
Fedorov, G.; Gayduchenko, I.; Titova, N.; Moskotin, M.; Obraztsova, E.; Rybin, M.; Goltsman, G. |
|
|
Title |
Graphene-based lateral Schottky diodes for detecting terahertz radiation |
Type |
Conference Article |
|
Year |
2018 |
Publication |
Proc. Optical Sensing and Detection V |
Abbreviated Journal |
Proc. Optical Sensing and Detection V |
|
|
Volume |
10680 |
Issue |
|
Pages |
30-39 |
|
|
Keywords |
graphene, terahertz radiation, detectors, Schottky diodes, carbon nanotubes, plasma waves |
|
|
Abstract |
Demand for efficient terahertz radiation detectors resulted in intensive study of the carbon nanostructures as possible solution for that problem. In this work we investigate the response to sub-terahertz radiation of graphene field effect transistors of two configurations. The devices of the first type are based on single layer CVD graphene with asymmetric source and drain (vanadium and gold) contacts and operate as lateral Schottky diodes (LSD). The devices of the second type are made in so-called Dyakonov-Shur configuration in which the radiation is coupled through a spiral antenna to source and top electrodes. We show that at 300 K the LSD detector exhibit the room-temperature responsivity from R = 15 V/W at f= 129 GHz to R = 3 V/W at f = 450 GHz. The DS detector responsivity is markedly lower (2 V/W) and practically frequency independent in the investigated range. We find that at low temperatures (77K) the graphene lateral Schottky diodes 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. The obtained data allows for determination of the most promising directions of development of the technology of nanocarbon structures for the detection of THz radiation. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Spie |
Place of Publication |
|
Editor |
Berghmans, F.; Mignani, A.G. |
|
|
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 |
10.1117/12.2307020 |
Serial |
1306 |
|
Permanent link to this record |
|
|
|
|
Author |
Gershenzon, E. M.; Goltsman, G.; Orlova, S.; Ptitsina, N.; Gurvich, Y. |
|
|
Title |
Germanium hot-electron narrow-band detector |
Type |
Journal Article |
|
Year |
1971 |
Publication |
Sov. Radio Engineering And Electronic Physics |
Abbreviated Journal |
Sov. Radio Engineering And Electronic Physics |
|
|
Volume |
16 |
Issue |
8 |
Pages |
1346 |
|
|
Keywords |
Ge HEB detectors |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Scripps Clinic Res Foundation 476 Prospect St, La Jolla, Ca 92037 |
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 |
1741 |
|
Permanent link to this record |
|
|
|
|
Author |
Trifonov, A.; Tong, C.-Y. E.; Lobanov, Y.; Kaurova, N.; Blundell, R.; Goltsman, G. |
|
|
Title |
Gap frequency and photon absorption in a hot electron bolometer |
Type |
Conference Article |
|
Year |
2016 |
Publication |
Proc. 27th Int. Symp. Space Terahertz Technol. |
Abbreviated Journal |
Proc. 27th Int. Symp. Space Terahertz Technol. |
|
|
Volume |
|
Issue |
|
Pages |
121 |
|
|
Keywords |
NbN HEB; Si membrane |
|
|
Abstract |
The superconducting energy gap is a crucial parameter of a superconductor when used in mixing applications. In the case of the SIS mixer, the mixing process is efficient for frequencies below the energy gap, whereas, in the case of the HEB mixer, the mixing process is most efficient at frequencies above the gap, where photon absorption takes place more readily. We have investigated the photon absorption phenomenon around the gap frequency of HEB mixers based on NbN films deposited on silicon membranes. Apart from studying the pumped I-V curves of HEB devices, we have also probed them with microwave radiation, as previously described [1]. At frequencies far below the gap frequency, the pumped I-V curves show abrupt switching between the superconducting and resistive states. For the NbN HEB mixers we tested, which have critical temperatures of ~9 K, this is true for frequencies below about 400 GHz. As the pump frequency is increased beyond 400 GHz, the resistive state extends towards zero bias and at some point a small region of negative differential resistance appears close to zero bias. In this region, the microwave probe reveals that the device impedance is changing randomly with time. As the pump frequency is further increased, this random impedance change develops into relaxation oscillations, which can be observed by the demodulation of the reflected microwave probe. Initially, these oscillations take the form of several frequencies grouped together under an envelope. As we approach the gap frequency, the multiple frequency relaxation oscillations coalesce into a single frequency of a few MHz. The resultant square-wave nature of the oscillation is a clear indication that the device is in a bi-stable state, switching between the superconducting and normal state. Above the gap frequency, it is possible to obtain a pumped I-V curve with no negative differential resistance above a threshold pumping level. Below this pumping level, the device demonstrates bi-stability, and regular relaxation oscillation at a few MHz is observed as a function of pump power. The threshold pumping level is clearly related to the amount of power absorbed by the device and its phonon cooling. From the above experiment, we can derive the gap frequency of the NbN film, which is 585 GHz for our 6 μm thin silicon membrane-based device. We also confirm that the HEB mixer is not an efficient photon absorber for radiation below the gap frequency. 1. A. Trifonov et al., “Probing the stability of HEB mixers with microwave injection”, IEEE Trans. Appl. Supercond., vol. 25, no. 3, June 2015. |
|
|
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 |
1204 |
|
Permanent link to this record |