Zobrazeno 1 - 10
of 24
pro vyhledávání: '"C.H. Worrall"'
Publikováno v:
Journal of Crystal Growth. 311:1923-1928
We report a comprehensive study into the growth of a 2.9 THz quantum cascade laser structure on two different molecular beam epitaxy manufacturers’ systems; within a single growth campaign and over multiple growth campaigns. Device performance figu
Autor:
C.H. Worrall, Harvey E. Beere, Carlo Sirtori, Jesse Alton, S. Whelan, Stefano Barbieri, David A. Ritchie
Publikováno v:
Journal of Crystal Growth. :935-940
The quantum cascade laser (QCL) is a powerful solid-state source of terahertz (THz) electromagnetic waves. We report a methodology by which the operating emission frequency of a THz QCL can be tuned by systematically altering the percentage thickness
Autor:
Owen P. Marshall, C.H. Worrall, Harvey E. Beere, David A. Ritchie, Stefano Barbieri, Jesse Alton
Publikováno v:
IEEE Photonics Technology Letters. 20:857-859
Distributed feedback quantum-cascade lasers based on loss-coupled two-metal gratings are presented. Devices lasing on single longitudinal modes between 2.62 and 2.69 THz are demonstrated, with sidemode suppression of 30 dB. In addition, controllable
Autor:
Vasilis Apostolopoulos, Joshua R. Freeman, C.H. Worrall, Harvey E. Beere, Jesse Alton, David A. Ritchie
Publikováno v:
Scopus-Elsevier
The laser emission frequencies of existing designs are controlled by uniform thickness transformations. Experimental results from a total of ten wafers are presented demonstrating a predictable shift in the emission wavelength concurrent with an anti
Autor:
Nenad Vukmirović, Harvey E. Beere, Carlo Sirtori, Edmund H. Linfield, H. Page, Zoran Ikonic, Dragan Indjin, C.H. Worrall, Xavier Marcadet, Paul Harrison, David A. Ritchie, V. D. Jovanović
Publikováno v:
Nonequilibrium Carrier Dynamics in Semiconductors ISBN: 9783540365877
The aim of this work is to report a detailed theoretical investigation, supported by the experimental measurements, of the influence of the injector doping level on the output characteristics and the working range limits in mid-infrared GaAs/AlGaAs q
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4323b1a11cee58b10861a498aa5c17e2
https://doi.org/10.1007/978-3-540-36588-4_19
https://doi.org/10.1007/978-3-540-36588-4_19
Autor:
C.H. Worrall, Carlo Sirtori, Harvey E. Beere, Mark Houghton, Jesse Alton, Stefano Barbieri, David A. Ritchie
Publikováno v:
SPIE Proceedings.
We report the operation of a 2 THz quantum cascade laser based on a GaAs/Al 0.1 Ga 0.9 As heterostructure. Lasing action takes place between an isolated subband and the upper state of a 14 meV wide miniband. In pulsed mode, with a 3.16mm long device,
Autor:
Alexander Giles Davies, Suraj P. Khanna, Harvey E. Beere, Edmund H. Linfield, David A. Ritchie, S. Chakraborty, T. Chakraborty, C.H. Worrall, John Fowler
Publikováno v:
Chakraborty, S, Chakraborty, T, Khanna, S P, Linfield, E H, Davies, A G, Fowler, J, Worrall, C H, Beere, H E & Ritchie, D A 2006, ' Spectral engineering of terahertz quantum cascade lasers using focused ion beam etched photonic lattices ', Electronics Letters, vol. 42, no. 7, pp. 404-405 . https://doi.org/10.1049/el:20064168
Focused ion beam etching has been used to introduce one-dimensional photonic lattices, of periods 9.11, 9.24, 9.44 /spl mu/m, between the cleaved facets of three 4.44 THz Fabry-Perot quantum cascade lasers. Singlemode lasing has been achieved at prec
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::66bc5b55c3a6aed1796cecea73110af9
Autor:
Harvey E. Beere, Alexander Giles Davies, S. Chakraborty, Edmund H. Linfield, John Fowler, Suraj P. Khanna, David A. Ritchie, T. Chakraborty, C.H. Worrall
Publikováno v:
2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference.
Focused ion beam etching has been used to introduce one-dimensional photonic crystals between the cleaved facets of terahertz quantum cascade lasers. These micro-structured lasers showed single-mode emission at specific wavelengths, governed by the r
Autor:
Harvey E. Beere, David A. Ritchie, Miriam S. Vitiello, Carlo Sirtori, C.H. Worrall, Stefano Barbieri, Jesse Alton, Vincenzo Spagnolo, Gaetano Scamarcio
Publikováno v:
Applied physics letters (Online) 89 (2006): 131114.
info:cnr-pdr/source/autori:Miriam S. Vitiello; Gaetano Scamarcio; Vincenzo Spagnolo; Chris Worrall; Harvey E. Beere; David A. Ritchie; Carlo Sirtori; Jesse Alton; Stefano Barbierib/titolo:Subband electronic temperatures and electron-lattice energy relaxation in terahertz quantum cascade lasers with different conduction band offsets/doi:/rivista:Applied physics letters (Online)/anno:2006/pagina_da:131114/pagina_a:/intervallo_pagine:131114/volume:89
Applied physics letters 89 (2006): 131114-1–131114-3. doi:10.1063/1.2357042
info:cnr-pdr/source/autori:Vitiello, MS; Scamarcio, G; Spagnolo, V; Worrall, C; Beere, HE; Ritchie, DA; Sirtori, C; Alton, J; Barbieri, S/titolo:Subband electronic temperatures and electron-lattice energy relaxation in terahertz quantum cascade lasers with different conduction band offsets/doi:10.1063%2F1.2357042/rivista:Applied physics letters/anno:2006/pagina_da:131114-1/pagina_a:131114-3/intervallo_pagine:131114-1–131114-3/volume:89
info:cnr-pdr/source/autori:Miriam S. Vitiello; Gaetano Scamarcio; Vincenzo Spagnolo; Chris Worrall; Harvey E. Beere; David A. Ritchie; Carlo Sirtori; Jesse Alton; Stefano Barbierib/titolo:Subband electronic temperatures and electron-lattice energy relaxation in terahertz quantum cascade lasers with different conduction band offsets/doi:/rivista:Applied physics letters (Online)/anno:2006/pagina_da:131114/pagina_a:/intervallo_pagine:131114/volume:89
Applied physics letters 89 (2006): 131114-1–131114-3. doi:10.1063/1.2357042
info:cnr-pdr/source/autori:Vitiello, MS; Scamarcio, G; Spagnolo, V; Worrall, C; Beere, HE; Ritchie, DA; Sirtori, C; Alton, J; Barbieri, S/titolo:Subband electronic temperatures and electron-lattice energy relaxation in terahertz quantum cascade lasers with different conduction band offsets/doi:10.1063%2F1.2357042/rivista:Applied physics letters/anno:2006/pagina_da:131114-1/pagina_a:131114-3/intervallo_pagine:131114-1–131114-3/volume:89
The electronic temperatures of the conduction subbands, the local lattice temperature, and the electron-lattice energy relaxation times (tau(E)) in bound-to-continuum GaAs/AlxGa1-xAs quantum cascade lasers, operating at 2.9 and 2 THz, are reported. T
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8de6902b1037d4ae2eb29fc66edb463c
http://hdl.handle.net/11589/2291
http://hdl.handle.net/11589/2291
Autor:
Stefano Barbieri, Jesse Alton, Mark Houghton, H. E. Beere, David A. Ritchie, C.H. Worrall, Edmund H. Linfield
Publikováno v:
Scopus-Elsevier
This study attempts to reduce the fast increase of threshold current densities J/sub TH/ with temperature by optimising the performance of a recently demonstrated superlattice QCL emitting at /spl lambda/ = 100 /spl mu/m using different active region