Browse by Author or creator
![]() | Up a level |
2020
Sutter, Jens U. and Lewis, Oliver and Robinson, Clive and McMahon, Anthony and Boyce, Robert and Bragg, Rachel and Macrae, Alastair and Orton, Jeffrey and Shah, Vishal and Ingleby, Stuart J. and Griffin, Paul F. and Riis, Erling (2020) Recording the heart beat of cattle using a gradiometer system of optically pumped magnetometers. Computers and Electronics in Agriculture, 177. 105651. ISSN 0168-1699
Elvin, Rachel and Wright, Michael W. and Lewis, Ben and Keliehor, Brendan L. and Bregazzi, Alan and McGilligan, James P. and Arnold, Aidan S. and Griffin, Paul F. and Riis, Erling (2020) Towards a compact, optically-interrogated, cold-atom microwave clock. Advanced Optical Technologies, 9 (5). pp. 297-303. ISSN 2192-8584
O'Dwyer, Carolyn and Ingleby, Stuart J. and Chalmers, Iain C. and Griffin, Paul F. and Riis, Erling (2020) A feed-forward measurement scheme for periodic noise suppression in atomic magnetometry. Review of Scientific Instruments, 91 (4). 045103. ISSN 0034-6748
Henderson, V. A. and Johnson, M. Y. H. and Kale, Y. B. and Griffin, P. F. and Riis, E. and Arnold, A. S. (2020) Optical characterisation of micro-fabricated Fresnel zone plates for atomic waveguides. Optics Express, 28 (7). pp. 9072-9081. ISSN 1094-4087
Elvin, Rachel and Hoth, Gregory W. and Wright, Michael and Lewis, Ben and Bregazzi, Alan and Keliehor, Brendan and Arnold, Aidan S. and Griffin, Paul F. and Riis, Erling; Shahriar, Selim M. and Scheuer, Jacob, eds. (2020) Progress of a compact microwave clock based on atoms cooled with a diffractive optic. In: Proceedings Optical, Opto-Atomic, and Entanglement-Enhanced Precision Metrology II. Proceedings of SPIE, 11296 . SPIE, USA, p. 1129609. ISBN 9781510633568
2019
Elvin, R. and Hoth, G. W. and Wright, M. and Lewis, B. and McGilligan, J. P. and Arnold, A. S. and Griffin, P. F. and Riis, E. (2019) Cold-atom clock based on a diffractive optic. Optics Express, 27 (26). pp. 38359-38366. ISSN 1094-4087
Janin, Paul and Bauer, Ralf and Griffin, Paul and Riis, Erling and Uttamchandani, Deepak (2019) Fast piezoelectric scanning MEMS mirror for 1D ion adressing. In: IEEE International Conference on Optical MEMS and Nanophotonics (OMN2019), 2019-07-28 - 2019-08-01, KAIST.
Hoth, Gregory W. and Elvin, Rachel and Wright, Michael and Lewis, Ben and Arnold, Aidan S. and Griffin, Paul F. and Riis, Erling (2019) Towards a compact atomic clock based on coherent population trapping and the grating magneto-optical trap. In: SPIE Photonics West OPTO, 2019-02-02 - 2019-02-07, San Francisco.
Akhtar, Mariam and Wilpers, Guido and Choonee, Kaushal and Riis, Erling and Sinclair, Alastair G (2019) Radio-frequency microplasmas with energies suited to in situ selective cleaning of surface adsorbates in ion microtraps. Journal of Physics B: Atomic, Molecular and Optical Physics, 52 (5). pp. 1-17. 055001. ISSN 0953-4075
2018
Offer, R. F. and Stulga, D. and Riis, E. and Franke-Arnold, S. and Arnold, A. S. (2018) Spiral bandwidth of four-wave mixing in Rb vapour. Communications Physics, 1. 84. ISSN 2399-3650
Hunter, Dominic and Jiménez-Martínez, Ricardo and Herbsommer, Juan and Ramaswamy, Srinath and Li, Wen and Riis, Erling (2018) Waveform reconstruction with a Cs based free-induction-decay magnetometer. Optics Express, 26 (23). pp. 30523-30531. ISSN 1094-4087
Sutter, Jens and Lewis, Oliver and Robinson, Clive and McMahon, Anthony and Boyce, Robert and Bragg, Rachel and Macrae, Alastair and Griffin, Paul and Riis, Erling and Ingleby, Stuart (2018) Recording the heart beat of cattle using a differential system of optically pumped magnetometers. In: Strathclyde Innovation Symposium on Optically Pumped Magnetometers, 2018-09-25 - 2018-09-26, Ross Priory.
Ingleby, Stuart J. and O'Dwyer, Carolyn and Griffin, Paul F. and Arnold, Aidan S. and Riis, Erling (2018) Vector magnetometry exploiting phase-geometry effects in a double-resonance alignment magnetometer. Physical Review Applied, 10 (3). 034035. ISSN 2331-7019
Janin, Paul and Bauer, Ralf and Griffin, Paul and Riis, Erling and Uttamchandani, Deepak (2018) Characterization of a fast piezoelectric varifocal MEMS mirror. In: Conference on Optical MEMS and Nanophotonics 2018, 2018-07-29 - 2018-08-02, Ecole Polyechnique Fédérale de Lausanne.
Elvin, Rachel and Hoth, Gregory W. and Wright, Michael W. and McGilligan, James P. and Arnold, Aidan S. and Griffin, Paul F. and Riis, Erling; (2018) Raman-Ramsey CPT with a grating magneto-optical trap. In: 2018 European Frequency and Time Forum (EFTF). IEEE, ITA, pp. 61-64. ISBN 9781538656204
Hunter, D. and Piccolomo, S. and Pritchard, J. D. and Brockie, N. L. and Dyer, T. E. and Riis, E. (2018) Free-induction-decay magnetometer based on a microfabricated Cs vapor cell. Physical Review Applied (10). 014002. ISSN 2331-7019
Thom, Joseph and Yuen, Ben and Wilpers, Guido and Riis, Erling and Sinclair, Alastair G. (2018) Intensity stabilisation of optical pulse sequences for coherent control of laser-driven qubits. Applied Physics B: Lasers and Optics, 124 (90). ISSN 0946-2171
Zhai, Y. and Carson, C. H. and Henderson, V. A. and Griffin, P. F. and Riis, E. and Arnold, A. S. (2018) Talbot-enhanced, maximum-visibility imaging of condensate interference. Optica, 5 (1). pp. 80-85. ISSN 1899-7015
2017
Ingleby, S. J. and Chalmers, I. C. and O'Dwyer, C. and Griffin, P. F. and Arnold, A. S. and Riis, E.; (2017) Optically pumped magnetometry in arbitrarily oriented magnetic fields. In: IEEE Sensors 2017. IEEE, GBR. ISBN 9781509010127
Robertson, Billy I. and MacKellar, Andrew R. and Halket, James and Gribbon, Anna and Pritchard, Jonathan D. and Arnold, Aidan S. and Riis, Erling and Griffin, Paul F. (2017) Detection of applied and ambient forces with a matter-wave magnetic gradiometer. Physical Review A - Atomic, Molecular, and Optical Physics, 96 (5). 053622. ISSN 1094-1622
Ingleby, Stuart and Riis, Erling and Arnold, Aidan and Griffin, Paul and O'Dwyer, Carolyn and Chalmers, Iain (2017) Double-resonance magnetometry in arbitrarily oriented fields. In: Workshop on Optically Pumped Magnetometers 2017, 2017-08-21 - 2017-08-22, University of Fribourg.
Ingleby, Stuart J. and O'Dwyer, Carolyn and Griffin, Paul F. and Arnold, Aidan S. and Riis, Erling (2017) Orientational effects on the amplitude and phase of polarimeter signals in double resonance atomic magnetometry. Physical Review A. ISSN 1094-1622 (In Press)
Macrae, C. D. and Fraczek, E. and Newton, M. E. and Dhillon, H. and Bennett, A. and Markham, M. and Diggle, P. and Breeze, B. G. and Dale, M. and Savitski, V. and Griffin, P. F. and Kemp, A. and Riis, E. and McConnell, G.; (2017) Optical detection of magnetic resonance in nitrogen vacancy centre ensembles in bulk diamond using an off-resonant probe laser beam. In: The European Conference on Lasers and Electro-Optics 2017. The Optical Society, DEU. ISBN 978-1-5090-6736-7
Ingleby, S. J. and Griffin, P. F. and Arnold, A. S. and Choulaira, Manto and Riis, E. (2017) High-precision control of static magnetic field magnitude, orientation, and gradient using optically pumped vapour cell magnetometry. Review of Scientific Instruments, 88 (4). 043109. ISSN 0034-6748
McGilligan, James P. and Griffin, Paul F. and Elvin, Rachel and Ingleby, Stuart J. and Riis, Erling and Arnold, Aidan S. (2017) Grating chips for quantum technologies. Scientific Reports, 7. 384. ISSN 2045-2322
2016
Arnold, Aidan and Griffin, Paul and Riis, Erling and Kale, Yogeshwar and Ingleby, Stuart and Henderson, Victoria and Elvin, Rachel and McGilligan, James Patrick (2016) Magnetometry optimisation in unshielded environments. In: 47th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics, 2016-05-23 - 2016-05-27, Rhode Island Convention Center.
Bongs, K. and Boyer, V. and Cruise, M. A. and Freise, A. and Holynski, M. and Hughes, J. and Kaushik, A. and Lien, Y.-H. and Niggebaum, A. and Perea-Ortiz, M. and Petrov, P. and Plant, S. and Singh, Y. and Stabrawa, A. and Paul, D. J. and Sorel, M. and Cumming, D. R. S. and Marsh, J. H. and Bowtell, R. W. and Bason, M. G. and Beardsley, R. P. and Campion, R. P. and Brookes, M. J. and Fernholz, T. and Fromhold, T. M. and Hackermuller, L. and Krüger, P. and Li, X. and Maclean, J. O. and Mellor, C. J. and Novikov, S. V. and Orucevic, F. and Rushforth, A. W. and Welch, N. and Benson, T. M. and Wildman, R. D. and Freegarde, T. and Himsworth, M. and Ruostekoski, J. and Smith, P. and Tropper, A. and Griffin, P. F. and Arnold, A. S. and Riis, E. and Hastie, J. E. and Paboeuf, D. and Parrotta, D. C. and Garraway, B. M. and Pasquazi, A. and Peccianti, M. and Hensinger, W. and Potter, E. and Nizamani, A. H. and Bostock, H. and Rodriguez Blanco, A. and Sinuco-Leon, G. and Hill, I. R. and Williams, R. A. and Gill, P. and Hempler, N. and Malcolm, G. P. A. and Cross, T. and Kock, B. O. and Maddox, S. and John, P.; Stuhler, Jürgen and Shields, Andrew J., eds. (2016) UK National Quantum Technologies Hub in sensors and metrology. In: Quantum Optics. Proceedings of SPIE . SPIE, BEL, 990009-1-990009-7.
Cotter, J. P. and McGilligan, J. P. and Griffin, P. F. and Rabey, I. M. and Docherty, K. and Riis, E. and Arnold, A. S. and Hinds, E. A. (2016) Design and fabrication of diffractive atom chips for laser cooling and trapping. Applied Physics B: Lasers and Optics, 122. ISSN 0946-2171
McGilligan, J. P. and Griffin, P. F. and Riis, E. and Arnold, A. S. (2016) Diffraction grating characterisation for cold-atom experiments. Journal of the Optical Society of America B, 33 (6). pp. 1271-1277. ISSN 0740-3224
Offer, Rachel F. and Conway, Johnathan W. C. and Riis, Erling and Franke-Arnold, Sonja and Arnold, Aidan S. (2016) Cavity-enhanced frequency up-conversion in rubidium vapour. Optics Letters, 41 (10). pp. 2177-2180. ISSN 0146-9592
McGilligan, James P. and Elvin, Rachel and Griffin, Paul F. and Riis, Erling and Arnold, Aidan S.; (2016) Utilising diffractive optics towards a compact, cold atom clock. In: European Frequency and Time Forum (EFTF), 2016. IEEE, GBR. ISBN 9781509007202
Henderson, V A and Griffin, P F and Riis, E and Arnold, A S (2016) Comparative simulations of Fresnel holography methods for atomic waveguides. New Journal of Physics, 18. 025007. ISSN 1367-2630
2015
McGilligan, J. P. and Griffin, P. F. and Riis, E. and Arnold, A. S. (2015) Phase-space properties of magneto-optical traps utilising micro-fabricated gratings. Optics Express, 23 (7). pp. 8948-8959. ISSN 1094-4087
McDonald, Alison and McConnell, Gail and Cox, David C. and Riis, Erling and Griffin, Paul F. (2015) 3D mapping of intensity field about the focus of a micrometer–scale parabolic mirror. Optics Express, 23 (3). pp. 2375-2382. ISSN 1094-4087
2013
Thom, Joseph and Wilpers, Guido and Riis, Erling and Sinclair, Alastair (2013) Accurate and agile digital control of optical phase, amplitude and frequency for coherent atomic manipulation of atomic systems. Optics Express, 21 (16). 18712–18723. ISSN 1094-4087
Nshii, Chidi and Vangeleyn, Matthieu and Cotter, J.P. and Griffin, Paul and Hinds, E.A. and Ironside, C.N. and See, P. and Sinclair, A G and Riis, Erling and Arnold, Aidan (2013) A surface-patterned chip as a strong source of ultracold atoms for quantum technologies. Nature Nanotechnology, 8 (5). pp. 321-324. ISSN 1748-3387
2012
Ackemann, T. and Alduraibi, M. and Campbell, S. and Keatings, S. and Sam, P. Luke and Fraser, H. and Arnold, A. S. and Riis, E. and Missous, M. (2012) Diamond heat sinking of terahertz antennas for continuous-wave photomixing. Journal of Applied Physics, 112 (12). 123109. ISSN 0021-8979
Pritchard, J. D. and Dinkelaker, A. N. and Arnold, A. S. and Griffin, P. F. and Riis, E. (2012) Demonstration of an inductively coupled ring trap for cold atoms. New Journal of Physics, 14. 103047. ISSN 1367-2630
2011
Dammalapati, U. and Norris, I. and Burrows, C. and Riis, E. (2011) Laser spectroscopy of the 4s4p(3) P-2-4s3d(1) D-2 transition on magnetically trapped calcium atoms. Physical Review A, 83 (6). 062513. ISSN 1094-1622
2010
Vangeleyn, Matthieu and Griffin, Paul F. and Riis, Erling and Arnold, Aidan S. (2010) Laser cooling with a single laser beam and a planar diffractor. Optics Letters, 35 (20). pp. 3453-3455. ISSN 0146-9592
Vernier, A. and Franke-Arnold, S. and Riis, E. and Arnold, A. S. (2010) Enhanced frequency up-conversion in Rb vapor. Optics Express, 18 (16). pp. 17020-17026. ISSN 1094-4087
Zawadzki, Mateusz Ernest and Griffin, P.F. and Riis, Erling and Arnold, A.S. (2010) Spatial interference from well-separated split condensates. Physical Review A, 81 (4). 043608. ISSN 1094-1622
Dammalapati, U. and Norris, I. and Burrows, C. and Arnold, A.S. and Riis, E. (2010) Spectroscopy and isotope shifts of the 4s3d 1D2–4s5p 1P1 repumping transition in magneto-optically trapped calcium atoms. Physical Review A, 81 (2). 023424. ISSN 1094-1622
Zhang, Wei and McDonald, Alison and Ackemann, Thorsten and Riis, Erling and McConnell, Gail (2010) Femtosecond synchronously in-well pumped vertical-external-cavity surface-emitting laser. Optics Express, 18 (1). pp. 187-192. ISSN 1094-4087
2009
Dammalapati, U. and Norris, I. and Maguire, L. and Borkowski, M. and Riis, E. (2009) A compact magneto-optical trap apparatus for calcium. Measurement Science and Technology, 20 (9). 095303. ISSN 0957-0233
Dammalapati, U. and Norris, I. and Riis, E., UK Engineering and Physical Sciences Research Council (EPSRC) (Funder) (2009) Saturated absorption spectroscopy of calcium in a hollow-cathode lamp. Journal of Physics B: Atomic, Molecular and Optical Physics, 42 (16). 165001. ISSN 0953-4075
Vangeleyn, Matthieu and Griffin, Paul F. and Riis, Erling and Arnold, Aidan S. (2009) Single-laser, one beam, tetrahedral magneto-optical trap. Optics Express, 17 (16). pp. 13601-13608. ISSN 1094-4087
Weatherill, K. J. and Pritchard, J. D. and Griffin, P. F. and Dammalapati, U. and Adams, C. S. and Riis, E. (2009) A versatile and reliably reusable ultrahigh vacuum viewport. Review of Scientific Instruments, 80 (2). 026105. ISSN 0034-6748
2008
Houston, N. and Riis, E. and Arnold, A.S. (2008) Reproducible dynamic dark ring lattices for ultracold atoms. Journal of Physics B: Atomic, Molecular and Optical Physics, 41 (21). 211001. ISSN 0953-4075
Esposito, E. and Keatings, Stefanie and Gardner, Kyle and Harris, J. and Riis, E. and McConnell, G. (2008) Confocal laser scanning microscopy using a frequency doubled vertical external cavity surface emitting laser. Review of Scientific Instruments, 79 (8). ISSN 0034-6748
Griffin, P.F. and Riis, E. and Arnold, A.S. (2008) Smooth inductively coupled ring trap for atoms. Physical Review A, 77 (5). 051402(R). ISSN 1094-1622
2007
Hopkins, J.M. and MacLean, A.J. and Burns, D. and Riis, E. and Schulz, N. and Rattunde, M. and Manz, C. and Kohler, K. and Wagner, J. (2007) Tunable, single-frequency, diode-pumped 2.3um VECSEL. Optics Express, 15 (13). pp. 8212-8217. ISSN 1094-4087
Morton, L.G. and Foreman, H.D. and Hastie, J.E. and Dawson, M.D. and Riis, E. (2007) Actively stabilised single-frequency red VECSEL. In: Advanced Solid State Photonics, ASSP 2007, 2007-01-28.
Hopkins, J.M. and Hempler, N. and MacLean, A.J. and Kemp, A. and Dawson, M.D. and Riis, E. and Schulz, N. and Rattunde, M. and Manzor, A.C.S. and Kohler, K. and Wagner, J. and Burns, D. (2007) High performance, GaSb-based, optically-pumped semiconductor disk lasers (invited). In: 8th International Conference on Mid-Infrared Optoelectronics: Materials and Devices, 2007-05-14 - 2007-05-16.
Ferguson, A.I. and McGinily, S.J. and Abram, R.H. and Gardner, K.S. and Riis, E. and Roberts, J.S. (2007) Novel GaIn medium design for short-wavelength vertical external-cavity surface-emitting laser. IEEE Journal of Quantum Electronics, 43. pp. 445-450. ISSN 0018-9197
2006
McGinily, Stephen J. and Abram, Richard H. and Riis, Erling and Ferguson, Allister I. (2006) Efficient coupling of several broad area laser diodes into an optical fiber. Review of Scientific Instruments, 77 (11). p. 116101. ISSN 0034-6748
Zhang, Wei and Ackemann, Thorsten and McGinily, Stephen and Schmid, Marc and Riis, Erling and Ferguson, Allister I. (2006) Operation of an optical in-well-pumped vertical-external-cavity surface-emitting laser. Applied Optics, 45 (29). pp. 7729-7735. ISSN 1559-128X
Arnold, A.S. and Garvie, C.S. and Riis, E. (2006) Large magnetic storage ring for Bose-Einstein condensates. Physical Review A, 73 (4). 041606(R). ISSN 1094-1622
Letchumanan, V and Gill, P and Sinclair, A G and Riis, E (2006) Optical-clock local-oscillator stabilization scheme. Journal of the Optical Society of America B, 23 (4). pp. 714-717. ISSN 0740-3224
2004
Riis, Erling and Sinclair, Alastair G. (2004) Optimum measurement strategies for trapped ion optical frequency standards. Journal of Physics B: Atomic, Molecular and Optical Physics, 37 (24). pp. 4719-4732. ISSN 0953-4075
Abram, Richard and Gardner, Kyle and Riis, Erling and Ferguson, Allister (2004) Narrow linewidth operation of a tunable optically pumped semiconductor laser. Optics Express, 12 (22). pp. 5434-5439. ISSN 1094-4087
McNeillie, Fiona and Riis, Erling and Broeng, Jes and Folkenberg, Jacob and Petersson, Anders and Simonsen, Harald and Jacobsen, Christian (2004) Highly polarized photonic crystal fiber laser. Optics Express, 12 (17). pp. 3981-3987. ISSN 1094-4087
Schmid, Marc and Benchabane, Sarah and Torabi-Goudarzi, Firuz and Abram, Richard and Ferguson, Allister I. and Riis, Erling (2004) Optical in-well pumping of a vertical-external-cavity surface-emitting laser. Applied Physics Letters, 84 (24). pp. 4860-4862. ISSN 0003-6951
McConnell, G. and Riis, E. (2004) Photonic crystal fibre enables short-wavelength two-photon laser scanning fluorescence microscopy with Fura-2. Physics in Medicine and Biology, 49 (20). pp. 4757-4763. ISSN 0031-9155
McConnell, G. and Riis, E. (2004) Two-photon laser scanning fluorescence microscopy using photonic crystal fibre. Journal of Biomedical Optics, 9 (5). pp. 922-927. ISSN 1083-3668
McConnell, G. and Riis, E. (2004) Ultra-short pulse compression using photonic crystal fibre. Applied Physics B: Lasers and Optics, 78 (5). pp. 557-563. ISSN 0946-2171
2003
Abram, Richard and Schmid, Marc and Riis, Erling and Ferguson, Allister; Hannaford, P and Sidorov, A and Bachor, H and Baldwin, K, eds. (2003) Optically pumped vecsels for high resolution spectroscopy : the new Ti : sapphire? In: Laser Spectroscopy. World Scientific Publishing Co. Pte Ltd, AUS, pp. 369-372. ISBN 9789812386168
Torabi-Goudarzi, Firuz and Riis, Erling (2003) Efficient cw high-power frequency doubling in periodically poled KTP. Optics Communications, 227 (4-6). pp. 389-403. ISSN 0030-4018
Hastie, J.E. and Hopkins, J.M. and Jeon, C.W. and Calvez, S. and Burns, D. and Dawson, M.D. and Abram, R.H. and Riis, E., IEEE, IEEE (2003) Microchip vertical external cavity surface-emitting lasers. IEEE Lasers and Electro-Optics Society Annual Meeting, 2. pp. 507-508. ISSN 1092-8081
Adams, C.S. and Cox, S.G. and Riis, E. and Arnold, A.S. (2003) Laser cooling of calcium in a 'golden ratio' quasi-electrostatic lattice. Journal of Physics B: Atomic, Molecular and Optical Physics, 36 (10). pp. 1933-1942. ISSN 0953-4075
Hastie, J.E. and Hopkins, J.M. and Calvez, S. and Jeon, C.W. and Burns, D. and Abram, R.H. and Riis, E. and Ferguson, A.I. and Dawson, M.D. (2003) 0.5-W single transverse-mode operation of an 850-nm diode-pumped surface-emitting semiconductor laser. IEEE Photonics Technology Letters, 15 (7). pp. 894-896. ISSN 1041-1135
Hastie, J.E. and Hopkins, J.M. and Jeon, C.W. and Calvez, S. and Burns, D. and Dawson, M.D. and Abram, R.H. and Riis, E. and Ferguson, A.I. and Alford, W.J. and Raymond, T.D. and Allerman, A.A. (2003) Microchip vertical external cavity surface emitting lasers. Electronics Letters, 39 (18). pp. 1324-1326. ISSN 0013-5194
2002
Balocchi, A. and Warburton, R.J. and Kutshera, H.J. and Karrai, K. and Abram, R.H. and Ferguson, A.I. and Calvez, S. and Dawson, M.D. and Riis, Erling (2002) A fiber-based vertically emitting semiconductor laser at 850nm. In: LEOS 2002. The 15th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2002, 2002-11-10 - 2002-11-14.
Arnold, A.S. and Riis, E. (2002) Bose-Einstein condensates in 'giant' toroidal magnetic traps. Journal of Modern Optics, 49 (5-6). pp. 959-964. ISSN 0950-0340
2001
Clarke, Roger B.M. and Kendon, Vivien M. and Chefles, Anthony and Barnett, Stephen M. and Riis, Erling and Sasaki, Masahide (2001) Experimental realization of optimal detection strategies for overcomplete states. Physical Review A, 64 (1). 012303-1-012303-13. ISSN 1094-1622
Clarke, Roger B.M. and Chefles, Anthony and Barnett, Stephen M. and Riis, Erling (2001) Experimental demonstration of optimal unambiguous state discrimination. Physical Review A, 63 (4). 040305-1-040305-4. ISSN 1094-1622