Home | [1–10] << 11 12 >> |
Records | |||||
---|---|---|---|---|---|
Author | Mitin, Vladimir; Antipov, Andrei; Sergeev, Andrei; Vagidov, Nizami; Eason, David; Strasser, Gottfried | ||||
Title | Quantum Dot Infrared Photodetectors: Photoresponse Enhancement Due to Potential Barriers | Type | Journal Article | ||
Year | 2011 | Publication | Nanoscale Research Letters | Abbreviated Journal | Nanoscale res lett |
Volume | 6 | Issue | 1 | Pages | 6 |
Keywords | Quantum dots; Infrared detectors; Photoresponse; Doping; Potential barriers; Capture processes | ||||
Abstract | Potential barriers around quantum dots (QDs) play a key role in kinetics of photoelectrons. These barriers are always created, when electrons from dopants outside QDs fill the dots. Potential barriers suppress the capture processes of photoelectrons and increase the photoresponse. To directly investigate the effect of potential barriers on photoelectron kinetics, we fabricated several QD structures with different positions of dopants and various levels of doping. The potential barriers as a function of doping and dopant positions have been determined using nextnano3 software. We experimentally investigated the photoresponse to IR radiation as a function of the radiation frequency and voltage bias. We also measured the dark current in these QD structures. Our investigations show that the photoresponse increases ~30 times as the height of potential barriers changes from 30 to 130 meV. | ||||
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 | RPLAB @ gujma @ | Serial | 712 | ||
Permanent link to this record | |||||
Author | Семенов, А. В.; Девятов, И. А.; Рябчун, С. А.; Масленников, С. Н.; Масленникова, А. С.; Ларионов, П. А.; Воронов, Б. М.; Чулкова, Г. М. | ||||
Title | Поглощение терагерцового электромагнитного излучения в “грязной” сверхпроводниковой пленке при произвольном виде спектральных функций | Type | Journal Article | ||
Year | 2011 | Publication | Ж. Радиоэлектрон. | Abbreviated Journal | |
Volume | 10 | Issue | Pages | 7 | |
Keywords | terahertz electromagnetic radiation; superconductors; detectors of terahertz range | ||||
Abstract | A problem of absorption of high-frequency electromagnetic field in dirty superconductor is treated within Keldysh technic. Expression for the source term in the kinetic equation for quasiparticle distribution function is derived. The result is significant for deriving a consistent microscopic theory of superconducting detectors for terahertz frequency range, perspective detectors on kinetic inductance of current-biased superconducting strip and on Josephson inductance of tunnel. В технике Келдыша рассмотрена задача о поглощении мощности высокочастотного электромагнитного поля в сверхпроводнике, удовлетворяющем условию грязного предела. Получено выражение для члена источника в кинетическом уравнении для функции распределения квазичастиц, справедливое при произвольном виде спектральных функций. Этот результат имеет значение для развития последовательной микроскопической теории сверхпроводниковых детекторов излучения терагерцового диапазона, в частности, перспективных детекторов на кинетической индуктивности смещённой током сверхпроводниковой полоски и джозефсоновской индуктивности туннельного контакта. |
||||
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 | Duplicated as 1117 | Approved | no | ||
Call Number | RPLAB @ gujma @ | Serial | 713 | ||
Permanent link to this record | |||||
Author | González, F. J.; Boreman, G. D. | ||||
Title | Comparison of dipole, bowtie, spiral and log-periodic IR antennas | Type | Journal Article | ||
Year | 2005 | Publication | Infrared Physics & Technology | Abbreviated Journal | Inf Phys & Technol |
Volume | 46 | Issue | 5 | Pages | 418-428 |
Keywords | optical antennas; Microbolometer; Infrared antennas; Antenna efficiency; Antenna-coupled detectors | ||||
Abstract | Antenna-coupled microbolometers use planar lithographic antennas to couple infrared radiation into a bolometer with sub-micron dimensions. In this paper four different types of infrared antennas were fabricated on thin grounded-substrates and coupled to microbolometers. Dipole, bowtie, spiral and log-periodic IR antenna-coupled detectors were measured at 10.6 μm and their performance compared. A new method to calculate the radiation efficiency based on the spatial and angular response of infrared antennas is presented and used to evaluate their performance. The calculated radiation efficiency for the dipole, bowtie, spiral and log-periodic IR antennas was 20%, 37%, 25% and 46% respectively. A dipole-length study was performed and shows that the quasistatic value of the effective permittivity accurately describes the incident wavelength in the substrate at infrared frequencies for antennas on a thin substrate. | ||||
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 | RPLAB @ gujma @ | Serial | 739 | ||
Permanent link to this record | |||||
Author | Shurakov, A.; Tong, Cheuk-yu E.; Grimes, P.; Blundell, R.; Golt'sman, G. | ||||
Title | A microwave reflection readout scheme for hot electron bolometric direct detector | Type | Journal Article | ||
Year | 2015 | Publication | IEEE Trans. THz Sci. Technol. | Abbreviated Journal | IEEE Trans. THz Sci. Technol. |
Volume | 5 | Issue | Pages | 81-84 | |
Keywords | HEB detectors | ||||
Abstract | In this paper, we propose and present data from a fast THz detector based on the repurpose of hot electron bolometer mixers (HEB) fabricated from superconducting NbN thinfilm. This detector is essentially a traditional NbN bolometer element that operates under the influence of a microwave pump. The in-jected microwave power serves the dual purpose of enhancing the detector sensitivity and reading out the impedance changes of the device in response to incidentTHz radiation. We have measured an optical Noise Equivalent Power of 4 pW/ Hz for our detector at a bath temperature of 4.2 K. The measurement frequency was 0.83 THz and the modulation frequency was 1.48 kHz. The readout scheme is versatile and facilitates both high-speed operation as well as multi-pixel applications. |
||||
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 | RPLAB @ atomics90 @ | Serial | 950 | ||
Permanent link to this record |