Outputs

Journal papers

Key: * Inter-group collaboration; + International collaboration; ^ Collaboration with other UK group

2024

+Non-contact imaging of terahertz surface currents with aperture-type near-field microscopy. S Norman, J Seddon, Y Lu, L Hale, A M Zaman, S Addamane, I Brener, R Degl’Innocenti, and O Mitrofanov. Optics Express (2024) in press. https://doi.org/10.1364/OE.531690

+Continuous wave terahertz detection using 1550 nm pumped nonlinear photoconductive GaAs metasurfaces. J Seddon, L Hale, H Jung, S Norman, I Brener, A Seeds, Cl Renaud, and O Mitrofanov. Optics Express 32, 9809–9819 (2024). https://doi.org/10.1364/OE.517422

+2D time-domain spectroscopy for determination of energy and momentum relaxation rates of hydrogen-like donor states in germanium. T B Gill, S G Pavlov, C Kidd, P Dean, A D Burnett, A Dunn, L H Li, N V Abrosimov, H-W Hubers, E H Linfield, A G Davies, and J R Freeman. ACS Photonics 11, 1447–1455 (2024). https://doi.org/10.1021/acsphotonics.3c01522

+^Harmonic generation in the Restrahlenband using a graphene split ring resonator array optically pumped by a semiconductor heterostructure laser. A Di Gaspare, C Schiattarella, C Song, L Li, A G Davies, E H Linfield, A C Ferrari, S Dhillon, and M S Vitiello. Nature Communications 15, 2312 (2024). https://doi.org/10.1038/s41467-024-45267-2

Microscopy of terahertz spoof surface plasmons propagating on planar metamaterial waveguides. N Sulollari, S Park, M Salih, P Rubino, A D Burnett, L Li, E H Linfield, A G Davies, J E Cunningham, and P Dean. APL Photonics 9, 031307 (2024). https://doi.org/10.1063/5.0190488

Terahertz microscopy using laser feedback interferometry based on a generalised phase-stepping algorithm. D Mohun, N Sulollari, M Salih, L H Li, J E Cunningham, E H Linfield, A G Davies, and P Dean. Scientific Reports 14, 3274 (2024). https://doi.org/10.1038/s41598-024-53448-8

+Sculpting harmonic comb states in terahertz quantum cascade lasers by controlled engineering. E Riccardi, M A J Guerrero, V Pistore, L Seitner, C Jirauschek, L Li, A G Davies, E H Linfield, and M S Vitiello. Optica 11, 412–419 (2024). https://doi.org/10.1364/OPTICA.509929

+Ultra-sensitive heterodyne detection at room temperature in the atmospheric windows. M Saemian, L Del Balzo, D Gacemi, Y Todorov, E Rodriguez, O Lopez, B Darquié, L Li, A G Davies, E Linfield, A Vasanelli, and C Sirtori. Nanophotonics (2024). https://doi.org/10.1515/nanoph-2023-0787

2023

Photoelectric tunable-step terahertz detectors: a study on optimal antenna parameters, speed, and temperature performance. R Chen, R Xia, J Griffiths, H E Beere, D A Ritchie, and W Michailow. Nanophotonics 13, 1917–1928. (2023). (Invited paper for the ITQW Special Issue). https://doi.org/10.1515/nanoph-2023-0864

Cylindrical multimode waveguides as focusing interferometric systems. W Michailow, N Almond, H Beere, and D Ritchie. ACS Photonics 10, 1756 (2023). https://doi.org/10.1021/acsphotonics.2c02030

^Achieving 100% amplitude modulation depth in a graphene-based tuneable capacitance metamaterial. R Xia, N W Almond, S J Kindness, SA Mikhailov, W Tadbier, R Degl’Innocenti, Y Lu, A Lowe, B Ramsay, L A Jakob, J Dann, S Hofmann, H E Beere, D A Ritchie, and W Michailow. arXiv: 2312.16330. https://doi.org/10.48550/arXiv.2312.16330

+Efficient THz generation from low-temperature-grown GaAs photoconductive antennas driven by Yb-doped fiber amplifier at 200 kHz repetition rate. N Nilforoushan, C Kidd, A Fournier, J Palomo, J Tignon, S Dhillon, E Lhuillier, L Li, A G Davies, E H Linfield, J R Freeman, and J Mangeney. Applied Physics Letters 123, 241107 (2023). https://doi.org/10.1063/5.0179419

*Enhanced delivery and detection of terahertz frequency radiation from a quantum cascade laser within dilution refrigerator. M Vaughan, W Michailow, M Tan, M Salih, L Li, H Beere, D A Ritchie, E H Linfield, A G Davies, and J E Cunningham. Journal of Low Temperature Physics 213, 306–316 (2023). https://doi.org/10.1007/s10909-023-03001-0

+^Electrically-tunable non-linearity at 3.2 THz in single layer graphene. A Di Gaspare, O Balci, J Zhang, S Shinde, L Li, A G Davies, E H Linfield, A C Ferrari, and M S Vitiello. ACS Photonics 10, 3171–3180 (2023). https://doi.org/10.1021/acsphotonics.3c00543

+Electronic transport driven by collective light-matter coupled states in a quantum device. F Pisani, D Gacemi, A Vasanelli, L Li, A G Davies, E Linfield, C Sirtori, and Y Todorov. Nature Communications 14, 3914 (2023). https://doi.org/10.1038/s41467-023-39594-z

+Electrically-pumped compact topological bulk lasers driven by band-inverted bound states in the continuum. S Han, J Cui, Y Chua, Y Zeng, L Hu, M Dai, F Wang, F Sun, S Zhu, L Li, A G Davies, E H Linfield, C S Tan, Y Kivshar, and Q J Wang. Light: Science & Applications 12, 145 (2023). https://doi.org/10.1038/s41377-023-01200-8

+Single-mode electrically pumped terahertz laser in an ultracompact cavity via merging bound states in the continuum. J Cui, Y Chua, S Han, C Wang, Y Jin, J Li, Y Zeng, Q Wang, M Ye, W Chen, S Zhu, F Sun, L Li, A G Davies, E H Linfield, C S Tan, and Q J Wang. Laser & Photonics Reviews 17, 2300350 (2023). https://doi.org/10.1002/lpor.202300350

^Acoustic band engineering in terahertz quantum-cascade lasers and arbitrary superlattices. A Demic, A Valavanis, P Dean, L Li, A G Davies, E H Linfield, J Cunningham, J Bailey, A Kent, and P Harrison. Physical Review B107, 235411 (2023). http://doi.org/10.1103/PhysRevB.107.235411

+Auto-calibrated charge sensitive infrared phototransistor at 9.3 µm. M Bahrehmand, D Gacemi, A Vasanelli, L Li, A G Davies, E Linfield, C Sirtori, and Y Todorov. Sensors 23, 3635 (2023). https://doi.org/10.3390/s23073635

+High-power density, single plasmon, terahertz quantum cascade lasers via transverse mode control. C Song, M Salih, L Li, J Mangeney, J Tignon, A G Davies, E Linfield, and S S Dhillon. Applied Physics Letters 122, 121108 (2023). https://doi.org/10.1063/5.0142359

+Short pulse generation from a graphene-coupled passive modelocked terahertz laser. E Riccardi, V Pistore, S Kang, Seitner, A de Vetter, C Jirauschek, J Mangeney, L Li, A G Davies, E H Linfield, A C Ferrari, S S Dhillon, and M S Vitiello. Nature Photonics (2023). https://doi.org/10.1038/s41566-023-01195-z

^Waveguide integration of a > 4.7-THz quantum-cascade laser. E Nuttall, Y Han, D Pardo, S S Kondawar, N Brewster, M Salih, L Li, M D Horbury, A G Davies, E H Linfield, H Wang, P Dean, B N Ellison, and A Valavanis. Electronics Letters 59, e12703 (2023). https://doi.org/10.1049/ell2.12703

^Determination of the permittivity of transmission lines at milli-Kelvin temperatures. M Stanley, R Parker-Jervis, J Skinner, S De Graaf, T Lindström, J E Cunningham, and N M Ridler. IEEE Access (2003). https://doi.org/10.1109/ACCESS.2023.3286374

Conference papers (selection)

2024

Study on the dependence of terahertz photoelectric tunable-step detector performance on antenna geometry. R. Chen, H.E. Beere, D.A. Ritchie, W. Michailow. 2024 Photonics and Electromagnetics Research Symposium (PIERS), Chengdu, China, April 2024. (Oral presentation)

*Developing free-space and polarization control of THz QCL radiation inside a dry dilution refrigerator. M Vaughan, W Michailow, R Xia, M Salih, L Li, H Beere, D Ritchie, E Linfield, G Davies, J Freeman, and J Cunningham. 49th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Perth, Australia (2024).

+High-power density, single-frequency terahertz quantum cascade lasers. M Salih, L Li, S Kondawar, J Freeman, G Davies, S Dhillon, and Edmund Linfield. 49th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Perth, Australia (2024).

2023

Generalized phase-extraction of amplitude and phase contrast in coherent THz-s-SNOM based on laser feedback interferometry. D Mohun, N Sulollari, M Salih, L Li, E H Linfield, A G Davies, J E Cunningham, and P Dean. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). https://doi.org/10.1109/IRMMW-THz57677.2023.10299074

+High-power density, single plasmon, terahertz quantum cascade lasers via transverse mode control. C Song, M Salih, L H Li, J Mangeney, J Tignon, A G Davies, E H Linfield, and S Dhillon. 48th International Conference on Infrared, illimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). https://doi.org/10.1109/IRMMW-THz57677.2023.10298954

Improved large area photoconductive antenna design for high field THz generation. C Kidd, M C Rosamond, T B Gill, L H Li, E H Linfield, A G Davies, and J R Freeman. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). https://doi.org/10.1109/IRMMW-THz57677.2023.10299215

^LT-GaAs metasurfaces as continuous-wave THz detectors operating in the telecommunications band. J Seddon, L Hale, H Jung, S Norman, S Addamane, I Brener, C Renaud, and O Mitrofanov. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). https://doi.org/10.1109/IRMMW-THz57677.2023.10299343

Influence of antenna parameters on terahertz photoelectric tunable-step detector operation. R. Chen, H.E. Beere, D.A. Ritchie, W. Michailow. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMWTHz), Montreal, Canada (2023). http://doi.org/10.1109/IRMMW-THz57677.2023.10299320

Solid-state intensity modulator based on a single-layer graphene-loaded metasurface operating at 2.2 THz. R. Xia, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. Oral Presentation. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). https://doi.org/10.1109/IRMMW-THz57677.2023.10299000

*+Improving the performance of THz delivery from a quantum cascade laser within a dry 3He dilution refrigerator. M. Vaughan, W. Michailow, M. Tan, M. Salih, L. Li, H. Beere, D. A. Ritchie, E. H. Linfield, A.G. Davies, J. E. Cunningham. Oral Presentation. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). http://doi.org/10.1109/IRMMW-THz57677.2023.10299280

+The in-plane photoelectric effect for terahertz detection in two- and quasi-one-dimensional electron systems. W. Michailow, S.A. Mikhailov, N.W. Almond, H.E. Beere, D.A. Ritchie. Oral Presentation. 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), Montreal, Canada (2023). http://doi.org/10.1109/IRMMW-THz57677.2023.10299185

Solid-state terahertz intensity modulator based on a single-layer graphene-metal metasurface. R. Xia, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. Emerging Imaging and Sensing Technologies for Security and Defence VIII 12740, 94 (2023). https://doi.org/10.1117/12.2679912

Investigation of the influence of antenna geometry on terahertz photoelectric tunable-step detector performance. R. Chen, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. Oral Presentation. Emerging Imaging and Sensing Technologies for Security and Defence VIII 12740, 98 (2023). https://doi.org/10.1117/12.2679876

Solid-state terahertz intensity modulator based on a single-layer graphene-metal metasurface. R. Xia, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. Invited talk. SPIE Sensors + Imaging conference, Amsterdam, The Netherlands, September 2023.

Investigation of the influence of antenna geometry on terahertz photoelectric tunable-step detector performance. R. Chen, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. Oral Presentation. SPIE Sensors + Imaging conference, Amsterdam, The Netherlands, September 2023.

+The in-plane photoelectric effect – a new opportunity for efficient terahertz detection. W. Michailow, S.A. Mikhailov, R. Xia, R. Chen, M. Tan, N.W. Almond, H.E. Beere, D.A. Ritchie. Invited talk. 10th International Symposium on Terahertz-Related Devices and Technologies – TeraTech 2023 conference, Aizu-Wakamatsu, Japan, September 2023. https://www.teratechconf.org/plenary-and-invited-speakers

The in-plane photoelectric effect – a new opportunity for efficient terahertz detection. W. Michailow, S.A. Mikhailov, R. Chen, R. Xia, N.W. Almond, H.E. Beere, D.A. Ritchie. Oral presentation. EP2DS-25/MSS-21, Grenoble, France, July 2023.

Single-layer graphene-loaded metasurface for terahertz intensity modulation. R. Xia, N.W. Almond, H.E. Beere, D.A. Ritchie, W. Michailow. EP2DS-25/MSS-21, Grenoble, France, July 2023.

Investigation of terahertz photoelectric tunable-step detectors: dependence of performance on antenna parameters. R. Chen, H.E. Beere, D.A. Ritchie, W. Michailow. EP2DS-25/MSS-21, Grenoble, France, July 2023.

Study of terahertz photoelectric tunable-step detectors: influence of antenna geometry on performance. R. Chen, H.E. Beere, D.A. Ritchie, W. Michailow. Oral presentation. Infrared and Terahertz Quantum Workshop (ITQW), Erice (Sicily), Italy, June 2023. https://itqw2023.nano.cnr.it/

Other outputs (selection: awards, new grants, public engagement, fellowships)

BeCurious Festival (University of Leeds, 18 March 2024): Large exhibition on the theme ‘What is it like being a laser scientist?’, led by Thomas Gill with support from nine Leeds PDRAs/PGRs, comprising several interactive activities on laser communication, spectroscopy, and the electromagnetic spectrum. Over 300 members of the public visited our display.

Joint EPSRC / DFG event with UK and German colleagues hosted by Leeds on 29 Feb and 1 March 2024 to explore collaborative programmes, several of relevance to TeraCom and terahertz communications.

Local school outreach (University of Leeds, 2023): Following an introductory visit to Roundhay School by Thomas Gill on 19 March 2023, twelve Roundhay School students from underrepresented groups visited the terahertz laboratory and the cleanroom on 25 May 2023, met with staff and students, and took part in demonstrations. They were set project work and returned to the university to present and discuss their findings on 18 July 2023.

TeraCom colleagues edited, and contributed to, ‘The 2023 Terahertz Science and Technology Roadmap’, Journal of Physics D: Applied Physics 56 (2023). https://doi.org/10.1088/1361-6463/acbe4c

Filming with the Cavendish communications team, N.W. Almond: https://www.youtube.com/watch?v=RpQEudXRvYM

“Delivering and focusing radiation using cylindrical tubes”, Blog post on the website of the Department of Physics, June 2023: https://www.phy.cam.ac.uk/blog/delivering-and-focusing-radiation-using-cylindrical-tubes