High power mm and sub-mm wave amplifiers for high frequency ESR/DNP, high resolution radar and remote sensing
Lead Research Organisation:
University of Strathclyde
Department Name: Physics
Abstract
In a gyrotron, electrons gyrating in a magnetic field are coupled to electromagnetic radiation in such a manner that the radiation is amplified by extracting the electron kinetic energy. We will investigate a novel concept which uses a helical corrugation on the inside surface of a 'cylindrical' waveguide to radically modify the wave dispersion giving eigenmodes with finite, constant group velocity in the region of near infinite phase velocity. This novel dispersion opens up for the first time the potential for a high power (5kW), broadband (10%), high gain >40dB, efficient (30%) gyrotron amplifier in the 90GHz to 100GHz frequency range and above. We have performed a preliminary experiment at X-band (8GHz to 10GHz) frequencies and will build on our lead to create an amplifier in the W-band (90GHz to 100GHz) frequency band based on the best understanding of this new concept and perform precision measurements of its gain, bandwidth, efficiency and stability against oscillations. New theory and computational models benchmarked against W-band experimental data will be used to demonstrate the potential for this novel amplifier to generate high frequency (360GHz to 400GHz and 460GHz to 500GHz), high power (~0.5kW), broadband (10%), pulsed and continuous coherent radiation crucially needed by the many known applications.
Publications
Michael McStravick (Author)
(2010)
5-fold helically corrugated waveguide dispersion measurements
McStravick M
(2010)
5-fold helically corrugated waveguide dispersion measurements
McElhinney P
(2012)
A broadband corrugated horn for a W-band gyro-TWA
Constable D
(2009)
A co-harmonic gyro-monotron with a novel corrugated interaction cavity
Constable D
(2009)
A co-harmonic gyro-oscillator with a novel interaction cavity
Donaldson C
(2012)
A cusp electron gun for millimeter wave gyro-devices
Donaldson C
(2010)
A cusp electron gun for millimeter wave gyrodevices
in Applied Physics Letters
Zhang L
(2011)
A four-stage depressed collector for a W-band gyro-BWO
McElhinney P
(2013)
A high directivity broadband corrugated horn for W-band gyro-devices
in IEEE Transactions on Antennas and Propagation
Constable DA
(2010)
A novel cylindrical TE(2,1) mode converter.
in The Review of scientific instruments
Wenlong He (Author)
(2010)
A W-band gyro-TWA using a helically corrugated waveguide
Donaldson C
(2011)
A W-band gyrotron traveling wave amplifier based on a cusp electron gun
Donaldson C
(2013)
A W-Band Multi-Layer Microwave Window for Pulsed Operation of Gyro-Devices
in IEEE Microwave and Wireless Components Letters
Zhang L
(2018)
Amplification of Frequency-Swept Signals in a -Band Gyrotron Travelling Wave Amplifier
in IEEE Electron Device Letters
Matheson K
(2011)
An X-band rectangular TE
Cairns R
(2009)
Beam-Plasma Interactions
He W
(2017)
Broadband Amplification of Low-Terahertz Signals Using Axis-Encircling Electrons in a Helically Corrugated Interaction Region.
in Physical review letters
Konoplev I
(2009)
Cherenkov maser based on a twodimensional periodic lattice
| Description | A high-power, W-band, millimetre-wave, 90-100GHz, novel helical waveguide tunable gyro-BWO has been designed, constructed and has been successfully operated. The corresponding gyro-amplifier has been designed and is under construction and measurement with the prospect of successful operation during 2013. The foundations have also been laid for further extension of these sources to even higher operating frequencies. Follow-on research projects involving applications of these novel sources in biomedical research and weather radars is starting. The performance of the W-band gyro-amplifier has been successfully measured and the results have been subsequently published in the high quality journal Physical Review Letters. DOI:https://doi.org/10.1103/PhysRevLett.119.184801 |
| Exploitation Route | The results of this gyro-device research can be applied in improving NMR sensitivity for biomedical research and in future cloud radars. |
| Sectors | Aerospace, Defence and Marine,Electronics,Energy,Environment,Pharmaceuticals and Medical Biotechnology,Other |
| URL | https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.119.184801 |
| Description | The interactions with industry based on the findings made during the period of research have continued to increase in the years after this award finished. Radiation sources and amplifiers, in the spectral region from microwave to terahertz, are extensively used in UK industry and public sectors such as security, defence, health and the environment. Companies, including e2v Technologies plc. (e2v) and TMD Technologies Ltd. (TMD), have developed and sold new radiation products based on post-1996 research undertaken at the University of Strathclyde. Their devices accessed new frequency ranges with considerable increases in power and bandwidth. The designs were transferred to industry, where devices have been constructed, jobs created, policy changed and considerable investments made. These sources have had extensive beneficial impact through applications in defence, surveillance, materials processing, health sciences and environmental monitoring. . |
| Sector | Aerospace, Defence and Marine,Electronics,Energy,Environment,Pharmaceuticals and Medical Biotechnology,Other |
| Impact Types | Societal,Economic |
| Description | Research Grant EOARD, AFOSR, USA |
| Amount | $150,000 (USD) |
| Funding ID | FA8655-13-1-2132 |
| Organisation | European Office of Aerospace Research & Development (EOARD) |
| Sector | Public |
| Country | United Kingdom |
| Start | 12/2012 |
| End | 12/2017 |
| Description | Services Rendered Grant for BAE Systems |
| Amount | £20,000 (GBP) |
| Organisation | BAE Systems |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 02/2014 |
| End | 03/2014 |
| Description | Services rendered research/advice/consultancy |
| Amount | £191,517 (GBP) |
| Organisation | BAE Systems |
| Sector | Academic/University |
| Country | United Kingdom |
| Start | 08/2016 |
| End | 03/2017 |
| Description | Joint research with Science & Technology Facilities Council (STFC) |
| Organisation | Science and Technologies Facilities Council (STFC) |
| Country | United Kingdom |
| Sector | Public |
| PI Contribution | University of Strathclyde researchers worked on this project with researchers from Science & Technology Facilities Council (STFC) |
| Collaborator Contribution | STFC researchers contributed their skill and expertise in constructing the novel helical waveguides. |
| Impact | Research reports and future collaborations |
| Start Year | 2009 |
| Description | Research collaboration with Institute of Applied Physics, RAS |
| Organisation | Russian Academy of Sciences |
| Department | Institute of Applied Physics |
| Country | Russian Federation |
| Sector | Academic/University |
| PI Contribution | Host : Hosting academic visitor : Several visits of researchers from the Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia to Strathclyde University for research collaborations. |
| Collaborator Contribution | Extensive research expertise in gyro-devices |
| Impact | Several publications in international refereed journals have joint-authorships arising out of this collaboration. |
| Description | Abdus Salam International Centre for Theoretical Physics, Trieste, Italy, Lecture to College in Plasma Physics |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Type Of Presentation | keynote/invited speaker |
| Geographic Reach | International |
| Primary Audience | Postgraduate students |
| Results and Impact | Invited speaker : Participation in conference : Invited presentation at the Abdus Salam International Centre for Theoretical Physics College in Plasma Physics 10-28 August 2009, Trieste, Italy "Long wavelength free electron lasers: modelling and experiments" .Abdus Salam International Centre for Theoretical Physics College in Plasma Physics Requests from international students to come to the University of Strathclyde to study and research. |
| Year(s) Of Engagement Activity | 2009 |
| URL | http://www.ictp.tv/eya/plasma09.php |
| Description | Invited Seminar at Glasgow University, Glasgow |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Type Of Presentation | keynote/invited speaker |
| Geographic Reach | Regional |
| Primary Audience | Undergraduate students |
| Results and Impact | Visitor : Invited talk : Invited Seminar at Glasgow University . Several enquiries from students interested in entering plasma physics as a research career. |
| Year(s) Of Engagement Activity | 2010 |
| Description | Research collaboration with Institute of Applied Physics, RAS, Nizhny Novgorod, Russsia |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Type Of Presentation | keynote/invited speaker |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Workshop Facilitator and Invited Keynote Speaker: International Scientific Workshops held in Russia in 2008, 2011 and 2014 Host : Hosting academic visitor : Several visits of researchers from the Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, Russia to Strathclyde University for research collaborations. . Several collaborative research papers were published in international refereed journals. |
| Year(s) Of Engagement Activity | Pre-2006,2006,2008,2011,2014 |
| Description | UK/Europe-China International Workshop |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Type Of Presentation | keynote/invited speaker |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | Keynote/plenary speaker : Key-note speaker and plenary lectures at conferences : Invited keynote paper at UK/Europe-China International Workshop on millimetre-waves and terahertz technologies "Recent Progress in High Power Millimetre-wave Sources at Strathclyde University"; 19-21 October 2009 , RAL, UK (Invited Keynote paper also given in the 1st Workshop held in Chengdu, China in 2008) UK/Europe-China International Workshop Increased research collaborations with research groups in China and attraction of research students to the UK and to the University of Strathclyde. |
| Year(s) Of Engagement Activity | 2008,2009,2010,2011,2012,2013,2014,2015 |
| URL | http://202.115.15.3/en/index/edit/pid/33 |