The genus Fomitopsis (Polyporales, Basidiomycota) reconsidered.

Based on seven- and three-gene datasets, we discuss four alternative approaches for a reclassification of Fomitopsidaceae (Polyporales, Basidiomycota). After taking into account morphological diversity in the family, we argue in favour of distinguishing three genera only, viz. Anthoporia, Antrodia and Fomitopsis. Fomitopsis becomes a large genus with 128 accepted species, containing almost all former Fomitopsis spp. and most species formerly placed in Antrodia, Daedalea and Laccocephalum. Genera Buglossoporus, Cartilosoma, Daedalea, Melanoporia, Neolentiporus, alongside twenty others, are treated as synonyms of Fomitopsis. This generic scheme allows for morphologically distinct genera in Fomitopsidaceae, unlike other schemes we considered. We provide arguments for retaining Fomitopsis and suppressing earlier (Daedalea, Caloporus) or simultaneously published generic names (Piptoporus) considered here as its synonyms. Taxonomy of nine species complexes in the genus is revised based on ITS, ITS + TEF1, ITS + TEF1 + RPB1 and ITS + TEF1 + RPB2 datasets. In total, 17 species are described as new to science, 26 older species are reinstated and 26 currently accepted species names are relegated to synonymy. A condensed identification key for all accepted species in the genus is provided. Taxonomic novelties: New species: Fomitopsis algumicola Grebenc & Spirin, F. caseosa Vlasák & Spirin, F. cupressicola Vlasák, J. Vlasák Jr. & Spirin, F. derelicta Vlasák & Spirin, F. dollingeri Vlasák & Spirin, F. fissa Vlasák & Spirin, F. lapidosa Miettinen & Spirin, F. lignicolor Vlasák & Spirin, F. maculosa Miettinen & Spirin, F. pannucea Runnel & Spirin, F. perhiemata Viner & Spirin, F. purpurea Spirin & Ryvarden, F. retorrida Spirin & Kotiranta, F. solaris Rivoire, A.M. Ainsworth & Vlasák, F. tristis Miettinen & Spirin, F. tunicata Miettinen & Spirin, F. visenda Miettinen & Spirin. New combinations: Fomitopsis aculeata (Cooke) Spirin & Miettinen, F. aethalodes (Mont.) Spirin, F. alaskana (D.V. Baxter) Spirin & Vlasák, F. albidoides (A. David & Dequatre) Bernicchia & Vlasák, F. amygdalina (Berk. & Ravenel) Spirin & Vlasák, F. angusta (Spirin & Vlasák) Spirin & Vlasák, F. atypa (Lév.) Spirin & Vlasák, F. caespitosa (Murrill) Spirin & Miettinen, F. calcitrosa (Spirin & Miettinen) Spirin & Miettinen, F. circularis (B.K. Cui & Hai J. Li) Spirin, F. concentrica (G. Cunn.) M.D. Barrett, F. cyclopis (Miettinen & Spirin) Miettinen & Spirin, F. dickinsii (Berk. ex Cooke) Spirin, F. elevata (Corner) Spirin & Miettinen, F. eucalypti (Kalchbr.) Spirin, F. ferrea (Cooke) Spirin & Viner, F. flavimontis (Vlasák & Spirin) Vlasák & Spirin, F. foedata (Berk.) Spirin & Miettinen, F. gilvidula (Bres.) Spirin & Miettinen, F. glabricystidia (Ipulet & Ryvarden) Miettinen & Ryvarden, F. globispora (Ryvarden & Aime) Spirin, F. hartmannii (Cooke) M.D. Barrett & Spirin, F. hyalina (Spirin, Miettinen & Kotir.) Spirin & Miettinen, F. hypoxantha (Bres.) Spirin & Miettinen, F. incana (Lév.) Spirin & V. Malysheva, F. infirma (Renvall & Niemelä) Miettinen & Niemelä, F. juniperina (Murrill) Spirin & Vlasák, F. kuzyana (Pilát ex Pilát) Spirin & Vlasák, F. leioderma (Mont.) Spirin & Vlasak, F. leucaena (Y.C. Dai & Niemelä) Spirin & Miettinen, F. luzonensis (Murrill) Spirin & Miettinen, F. maculatissima (Lloyd) Spirin, F. madronae (Vlasák & Ryvarden) Vlasák & Ryvarden, F. malicola (Berk. & M.A. Curtis) Spirin, F. marchionica (Mont.) Spirin & Miettinen, F. marianii (Bres.) Spirin, Vlasák & Cartabia, F. mellita (Niemelä & Penttilä) Niemelä & Miettinen, F. microcarpa (B.K. Cui & Shun Liu) Spirin, F. micropora (B.K. Cui & Shun Liu) Spirin, F. modesta (Kuntze ex Fr.) Vlasák & Spirin, F. monomitica (Yuan Y. Chen) Spirin & Viner, F. morganii (Lloyd) Spirin & Vlasák, F. moritziana (Lév.) Spirin & Miettinen, F. neotropica (D.L. Lindner, Ryvarden & T.J. Baroni) Vlasák, F. nigra (Berk.) Spirin & Miettinen, F. nivosella (Murrill) Spirin & Vlasák, F. oboensis (Decock, Amalfi & Ryvarden) Spirin, F. oleracea (R.W. Davidson & Lombard) Spirin & Vlasák, F. philippinensis (Murrill) Spirin & Vlasák, F. primaeva (Renvall & Niemelä) Miettinen & Niemelä, F. psilodermea (Berk. & Mont.) Spirin & Vlasák, F. pulverulenta (Rivoire) Rivoire, F. pulvina (Pers.) Spirin & Vlasák, F. pulvinascens (Pilát ex Pilát) Niemelä & Miettinen, F. quercina (L.) Spirin & Miettinen, F. ramentacea (Berk. & Broome) Spirin & Vlasák, F. renehenticii (Rivoire, Trichies & Vlasák) Rivoire & Vlasák, F. roseofusca (Romell) Spirin & Vlasák, F. sagraeana (Mont.) Vlasák & Spirin, F. sandaliae (Bernicchia & Ryvarden) Bernicchia & Vlasák, F. sclerotina (Rodway) M.D. Barrett & Spirin, F. serialiformis (Kout & Vlasák) Vlasák, F. serialis (Fr.) Spirin & Runnel, F. serrata (Vlasák & Spirin) Vlasák & Spirin, F. squamosella (Bernicchia & Ryvarden) Bernicchia & Ryvarden, F. stereoides (Fr.) Spirin, F. subectypa (Murrill) Spirin & Vlasák, F. substratosa (Malençon) Spirin & Miettinen, F. tropica (B.K. Cui) Spirin, F. tumulosa (Cooke) M.D. Barrett & Spirin, F. tuvensis (Spirin, Vlasák & Kotir.) Spirin & Vlasák, F. uralensis (Pilát) Spirin & Miettinen, F. ussuriensis (Bondartsev & Ljub.) Spirin & Miettinen, F. variiformis (Peck) Vlasák & Spirin, F. yunnanensis (M.L. Han & Q. An) Spirin, Daedaleopsis candicans (P. Karst.) Spirin, Megasporoporia eutelea (Har. & Pat.) Spirin & Viner, Neofomitella hemitephra (Berk.) M.D. Barrett, Pseudophaeolus soloniensis (Dubois) Spirin & Rivoire, P. trichrous (Berk. & M.A. Curtis) Vlasák & Spirin. New synonyms: Antrodia bondartsevae Spirin, A. huangshanensis Y.C. Dai & B.K. Cui, A. taxa T.T. Chang & W.N. Chou, A. wangii Y.C. Dai & H.S. Yuan, Antrodiella subnigra Oba, Mossebo & Ryvarden, Antrodiopsis Audet, Boletus quercinus Schrad., Brunneoporus Audet, Buglossoporus Kotl. & Pouzar, Buglossoporus eucalypticola M.L. Han, B.K. Cui & Y.C. Dai, Caloporus P. Karst., Cartilosoma Kotlaba & Pouzar, Coriolus clemensiae Murrill, C. cuneatiformis Murrill, C. hollickii Murrill, C. parthenius Hariot & Pat., C. rubritinctus Murrill, Daedalea Pers., Daedalea allantoidea M.L. Han, B.K. Cui & Y.C. Dai, D. americana M.L. Han, Vlasák & B.K. Cui, D. radiata B.K. Cui & Hai J. Li, D. rajchenbergiana Kossmann & Drechsler-Santos, D. sinensis Lloyd, Daedalella B.K. Cui & Shun Liu, Dentiporus Audet, Flavidoporia Audet, Fomes subferreus Murrill, Fomitopsis cana B.K. Cui, Hai J. Li & M.L. Han, F. caribensis B.K. Cui & Shun Liu, F. cystidiata B.K. Cui & M.L. Han, F. ginkgonis B.K. Cui & Shun Liu, F. iberica Melo & Ryvarden, F. incarnata K.M. Kim, J.S. Lee & H.S. Jung, F. subfeei B.K. Cui & M.L. Han, F. subtropica B.K. Cui & Hai J. Li, Fragifomes B.K. Cui, M.L. Han & Y.C. Dai, Leptoporus epileucinus Pilát, Melanoporia Murrill, Neoantrodia Audet, Neolentiporus Rajchenb., Nigroporus macroporus Ryvarden & Iturr., Niveoporofomes B.K. Cui, M.L. Han & Y.C. Dai, Pilatoporus Kotl. & Pouzar, Piptoporus P. Karst., Polyporus aurora Ces., P. durescens Overh. ex J. Lowe, P. griseodurus Lloyd, Poria incarnata Pers., Pseudoantrodia B.K. Cui, Y.Y. Chen & Shun Liu, Pseudofomitopsis B.K. Cui & Shun Liu, Ranadivia Zmitr., Rhizoporia Audet, Rhodofomes Kotl. & Pouzar, Rhodofomitopsis B.K. Cui, M.L. Han & Y.C. Dai, Rhodofomitopsis pseudofeei B.K. Cui & Shun Liu, R. roseomagna Nogueira-Melo, A.M.S. Soares & Gibertoni, Rubellofomes B.K. Cui, M.L. Han & Y.C. Dai, Subantrodia Audet, Trametes fulvirubida Corner, T. lignea Murrill, T. lusor Corner, T. pseudodochmia Corner, T. subalutacea Bourdot & Galzin, T. supermodesta Ryvarden & Iturr., T. tuberculata Bres., Tyromyces multipapillatus Corner, T. ochraceivinosus Corner, T. palmarum Murrill, T. singularis Corner, T. squamosellus Núñez & Ryvarden, Ungulidaedalea B.K. Cui, M.L. Han & Y.C. Dai. Lectotypes: Hexagonia sulcata Berk., Polyporus castaneae Bourdot & Galzin, Poria incarnata Pers., Trametes subalutacea Bourdot & Galzin, Ungulina substratosa Malençon. Neotypes: Agaricus soloniensis Dubois, Boletus pulvinus Pers. Citation: Spirin V, Runnel K, Vlasák J, Viner I, Barrett MD, Ryvarden L, Bernicchia A, Rivoire B, Ainsworth AM, Grebenc T, Cartabia M, Niemelä T, Larsson K-H, Miettinen O (2024). The genus Fomitopsis (Polyporales, Basidiomycota) reconsidered. Studies in Mycology 107: 149-249. doi: 10.3114/sim.2024.107.03.

Fungal Planet description sheets: 1042-1111.

Novel species of fungi described in this study include those from various countries as follows: Antarctica, Cladosporium arenosum from marine sediment sand. Argentina, Kosmimatamyces alatophylus (incl. Kosmimatamyces gen. nov.) from soil. Australia, Aspergillus banksianus, Aspergillus kumbius, Aspergillus luteorubrus, Aspergillus malvicolor and Aspergillus nanangensis from soil, Erysiphe medicaginis from leaves of Medicago polymorpha, Hymenotorrendiella communis on leaf litter of Eucalyptus bicostata, Lactifluus albopicri and Lactifluus austropiperatus on soil, Macalpinomyces collinsiae on Eriachne benthamii, Marasmius vagus on soil, Microdochium dawsoniorum from leaves of Sporobolus natalensis, Neopestalotiopsis nebuloides from leaves of Sporobolus elongatus, Pestalotiopsis etonensis from leaves of Sporobolus jacquemontii, Phytophthora personensis from soil associated with dying Grevillea mccutcheonii. Brazil, Aspergillus oxumiae from soil, Calvatia baixaverdensis on soil, Geastrum calycicoriaceum on leaf litter, Greeneria kielmeyerae on leaf spots of Kielmeyera coriacea. Chile, Phytophthora aysenensis on collar rot and stem of Aristotelia chilensis. Croatia, Mollisia gibbospora on fallen branch of Fagus sylvatica. Czech Republic, Neosetophoma hnaniceana from Buxus sempervirens. Ecuador, Exophiala frigidotolerans from soil. Estonia, Elaphomyces bucholtzii in soil. France, Venturia paralias from leaves of Euphorbia paralias. India, Cortinarius balteatoindicus and Cortinarius ulkhagarhiensis on leaf litter. Indonesia, Hymenotorrendiella indonesiana on Eucalyptus urophylla leaf litter. Italy, Penicillium taurinense from indoor chestnut mill. Malaysia, Hemileucoglossum kelabitense on soil, Satchmopsis pini on dead needles of Pinus tecunumanii. Poland, Lecanicillium praecognitum on insects' frass. Portugal, Neodevriesia aestuarina from saline water. Republic of Korea, Gongronella namwonensis from freshwater. Russia, Candida pellucida from Exomias pellucidus, Heterocephalacria septentrionalis as endophyte from Cladonia rangiferina, Vishniacozyma phoenicis from dates fruit, Volvariella paludosa from swamp. Slovenia, Mallocybe crassivelata on soil. South Africa, Beltraniella podocarpi, Hamatocanthoscypha podocarpi, Coleophoma podocarpi and Nothoseiridium podocarpi (incl. Nothoseiridium gen. nov.) from leaves of Podocarpus latifolius, Gyrothrix encephalarti from leaves of Encephalartos sp., Paraphyton cutaneum from skin of human patient, Phacidiella alsophilae from leaves of Alsophila capensis, and Satchmopsis metrosideri on leaf litter of Metrosideros excelsa. Spain, Cladophialophora cabanerensis from soil, Cortinarius paezii on soil, Cylindrium magnoliae from leaves of Magnolia grandiflora, Trichophoma cylindrospora (incl. Trichophoma gen. nov.) from plant debris, Tuber alcaracense in calcareus soil, Tuber buendiae in calcareus soil. Thailand, Annulohypoxylon spougei on corticated wood, Poaceascoma filiforme from leaves of unknown Poaceae. UK, Dendrostoma luteum on branch lesions of Castanea sativa, Ypsilina buttingtonensis from heartwood of Quercus sp. Ukraine, Myrmecridium phragmiticola from leaves of Phragmites australis. USA, Absidia pararepens from air, Juncomyces californiensis (incl. Juncomyces gen. nov.) from leaves of Juncus effusus, Montagnula cylindrospora from a human skin sample, Muriphila oklahomaensis (incl. Muriphila gen. nov.) on outside wall of alcohol distillery, Neofabraea eucalyptorum from leaves of Eucalyptus macrandra, Diabolocovidia claustri (incl. Diabolocovidia gen. nov.) from leaves of Serenoa repens, Paecilomyces penicilliformis from air, Pseudopezicula betulae from leaves of leaf spots of Populus tremuloides. Vietnam, Diaporthe durionigena on branches of Durio zibethinus and Roridomyces pseudoirritans on rotten wood. Morphological and culture characteristics are supported by DNA barcodes.

Precision Measurements of the

Measurement of the ^{138}Ba^{+} ^{2}S_{1/2}-^{2}D_{5/2} clock transition frequency and D_{5/2} Landé g_{J} factor are reported. The clock transition frequency ν_{Ba^{+}}=170126432449333.31±(0.39)_{stat}±(0.29)_{sys} Hz, is obtained with accuracy limited by the frequency calibration of the maser used as a reference oscillator. The Landé g_{J} factor for the ^{2}D_{5/2} level is determined to be g_{D}=1.20036739(24), which is a 30-fold improvement on previous measurements. The g-factor measurements are corrected for an ac-magnetic field from trap-drive-induced currents in the electrodes, and data taken over a range of magnetic fields underscores the importance of accounting for this systematic.

Hyperfine Averaging by Dynamic Decoupling in a Multi-Ion Lutetium Clock.

We propose and experimentally demonstrate a scheme that realizes hyperfine averaging during a Ramsey interrogation of a clock transition. The method eliminates the need to average over multiple optical transitions, reduces the sensitivity of the clock to its environment, and reduces inhomogeneous broadening in a multi-ion clock. The method is compatible with autobalanced Ramsey spectroscopy, which facilitates the elimination of residual shifts due to imperfect implementation and ac stark shifts from the optical probe. We demonstrate the scheme using correlation spectroscopy of the ^{1}S_{0}↔^{3}D_{1} clock transition in a three-ion Lu^{+} clock. From the demonstration we are able to provide a measurement of the ^{3}D_{1} quadrupole moment, Θ(^{3}D_{1})=0.634(9)ea_{0}^{2}.

Suppressing Inhomogeneous Broadening in a Lutetium Multi-ion Optical Clock.

We demonstrate precision measurement and control of inhomogeneous broadening in a multi-ion clock consisting of three ^{176}Lu^{+} ions. Microwave spectroscopy between hyperfine states in the ^{3}D_{1} level is used to characterize differential systematic shifts between ions, most notably those associated with the electric quadrupole moment. By appropriate alignment of the magnetic field, we demonstrate suppression of these effects to the ∼10^{-17} level relative to the ^{1}S_{0}↔^{3}D_{1} optical transition frequency. Correlation spectroscopy on the optical transition demonstrates the feasibility of a 10-s Ramsey interrogation in the three ion configuration with a corresponding projection noise limited stability of σ(τ)=8.2×10^{-17}/sqrt[τ].

Blackbody radiation shift assessment for a lutetium ion clock.

The accuracy of state-of-the-art atomic clocks is derived from the insensitivity of narrow optical atomic resonances to environmental perturbations. Two such resonances in singly ionized lutetium have been identified with potentially lower sensitivities compared to other clock candidates. Here we report measurement of the most significant unknown atomic property of both transitions, the static differential scalar polarizability. From this, the fractional blackbody radiation shift for one of the transitions is found to be -1.36(9) × 10-18 at 300 K, the lowest of any established optical atomic clock. In consideration of leading systematic effects common to all ion clocks, both transitions compare favorably to the most accurate ion-based clocks reported to date. This work firmly establishes Lu+ as a promising candidate for a future generation of more accurate optical atomic clocks.

Cavity QED Engineering of Spin Dynamics and Squeezing in a Spinor Gas.

We propose a method for engineering spin dynamics in ensembles of integer-spin atoms confined within a high-finesse optical cavity. Our proposal uses cavity-assisted Raman transitions to engineer a Dicke model for integer-spin atoms, which, in a dispersive limit, reduces to effective atom-atom interactions within the ensemble. This scheme offers a promising and flexible new avenue for the exploration of a wide range of spinor many-body physics. As an example of this, we present results showing that this method can be used to generate spin-nematic squeezing in an ensemble of spin-1 atoms. With realistic parameters, the scheme should enable substantial squeezing on time scales much shorter than current experiments with spin-1 Bose-Einstein condensates.

Suppression of Clock Shifts at Magnetic-Field-Insensitive Transitions.

We show that it is possible to significantly reduce rank 2 tensor shifts of a clock transition by operating at a judiciously chosen magnetic-field-insensitive point. In some cases shifts are almost completely eliminated making the transition an effective J=0 to J=0 candidate. This significantly improves the feasibility of a recent proposal for clock operation with large ion crystals. For such multi-ion clocks, geometric constraints and selection rules naturally divide clock operation into two categories based on the orientation of the magnetic field. We discuss the limitations imposed on each type and how calibrations might be carried out for clock operation.

Systematic evaluation of an atomic clock at 2 × 10(-18) total uncertainty.

The pursuit of better atomic clocks has advanced many research areas, providing better quantum state control, new insights in quantum science, tighter limits on fundamental constant variation and improved tests of relativity. The record for the best stability and accuracy is currently held by optical lattice clocks. Here we take an important step towards realizing the full potential of a many-particle clock with a state-of-the-art stable laser. Our (87)Sr optical lattice clock now achieves fractional stability of 2.2 × 10(-16) at 1 s. With this improved stability, we perform a new accuracy evaluation of our clock, reducing many systematic uncertainties that limited our previous measurements, such as those in the lattice ac Stark shift, the atoms' thermal environment and the atomic response to room-temperature blackbody radiation. Our combined measurements have reduced the total uncertainty of the JILA Sr clock to 2.1 × 10(-18) in fractional frequency units.

Fungal Planet description sheets: 154-213.

Novel species of microfungi described in the present study include the following from South Africa: Camarosporium aloes, Phaeococcomyces aloes and Phoma aloes from Aloe, C. psoraleae, Diaporthe psoraleae and D. psoraleae-pinnatae from Psoralea, Colletotrichum euphorbiae from Euphorbia, Coniothyrium prosopidis and Peyronellaea prosopidis from Prosopis, Diaporthe cassines from Cassine, D. diospyricola from Diospyros, Diaporthe maytenicola from Maytenus, Harknessia proteae from Protea, Neofusicoccum ursorum and N. cryptoaustrale from Eucalyptus, Ochrocladosporium adansoniae from Adansonia, Pilidium pseudoconcavum from Greyia radlkoferi, Stagonospora pseudopaludosa from Phragmites and Toxicocladosporium ficiniae from Ficinia. Several species were also described from Thailand, namely: Chaetopsina pini and C. pinicola from Pinus spp., Myrmecridium thailandicum from reed litter, Passalora pseudotithoniae from Tithonia, Pallidocercospora ventilago from Ventilago, Pyricularia bothriochloae from Bothriochloa and Sphaerulina rhododendricola from Rhododendron. Novelties from Spain include Cladophialophora multiseptata, Knufia tsunedae and Pleuroascus rectipilus from soil and Cyphellophora catalaunica from river sediments. Species from the USA include Bipolaris drechsleri from Microstegium, Calonectria blephiliae from Blephilia, Kellermania macrospora (epitype) and K. pseudoyuccigena from Yucca. Three new species are described from Mexico, namely Neophaeosphaeria agaves and K. agaves from Agave and Phytophthora ipomoeae from Ipomoea. Other African species include Calonectria mossambicensis from Eucalyptus (Mozambique), Harzia cameroonensis from an unknown creeper (Cameroon), Mastigosporella anisophylleae from Anisophyllea (Zambia) and Teratosphaeria terminaliae from Terminalia (Zimbabwe). Species from Europe include Auxarthron longisporum from forest soil (Portugal), Discosia pseudoartocreas from Tilia (Austria), Paraconiothyrium polonense and P. lycopodinum from Lycopodium (Poland) and Stachybotrys oleronensis from Iris (France). Two species of Chrysosporium are described from Antarctica, namely C. magnasporum and C. oceanitesii. Finally, Licea xanthospora is described from Australia, Hypochnicium huinayensis from Chile and Custingophora blanchettei from Uruguay. Novel genera of Ascomycetes include Neomycosphaerella from Pseudopentameris macrantha (South Africa), and Paramycosphaerella from Brachystegia sp. (Zimbabwe). Novel hyphomycete genera include Pseudocatenomycopsis from Rothmannia (Zambia), Neopseudocercospora from Terminalia (Zambia) and Neodeightoniella from Phragmites (South Africa), while Dimorphiopsis from Brachystegia (Zambia) represents a novel coelomycetous genus. Furthermore, Alanphillipsia is introduced as a new genus in the Botryosphaeriaceae with four species, A. aloes, A. aloeigena and A. aloetica from Aloe spp. and A. euphorbiae from Euphorbia sp. (South Africa). A new combination is also proposed for Brachysporium torulosum (Deightoniella black tip of banana) as Corynespora torulosa. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.

Spectroscopy on a single trapped ¹³7Ba⁺ ion for nuclear magnetic octupole moment determination.

We present precision measurements of the hyperfine intervals in the 5D3/2 manifold of a single trapped Barium ion, ¹³7Ba⁺. Measurements of the hyperfine intervals are made between mF = 0 sublevels over a range of magnetic fields allowing us to interpolate to the zero field values with an accuracy below a few Hz, an improvement on previous measurements by three orders of magnitude. Our results, in conjunction with theoretical calculations, provide a 30-fold reduction in the uncertainty of the magnetic dipole (A) and electric quadrupole (B) hyperfine constants. In addition, we obtain the magnetic octupole constant (C) with an accuracy below 0.1Hz. This gives a subsequent determination of the nuclear magnetic octupole moment, Ω, with an uncertainty of 1% limited almost completely by the accuracy of theoretical calculations. This constitutes the first observation of the octupole moment in ¹³7Ba⁺ and the most accurately determined octupole moment to date.

Self-organization threshold scaling for thermal atoms coupled to a cavity.

We make a detailed experimental study of the threshold for the self-organization of thermal 87Rb atoms coupled to a high-finesse cavity over a range of atom numbers and cavity detunings. We investigate the difference between probing with a traveling wave and a retroreflected lattice. These two scenarios lead to qualitatively different behavior in terms of the response of the system as a function of cavity detuning with respect to the probe. In both cases, we confirm a N(-1) scaling of the threshold with atom number.

Intra-abdominal femoral nerve reconstruction following excision during right hemicolectomy.

Iatrogenic femoral nerve injury is an uncommon but recognised complication of abdominal and gynaecological surgery. There have been several reported cases following colorectal surgery which specifically report transient femoral nerve neuropathies with variable but often full recovery. To our knowledge, this is the first documented case of femoral nerve reconstruction after iatrogenic resection during right hemicolectomy. We present a case report of complete femoral nerve transection following abdominal surgery and discuss our management.

Implementation of the semiclassical quantum Fourier transform in a scalable system.

We report the implementation of the semiclassical quantum Fourier transform in a system of three beryllium ion qubits (two-level quantum systems) confined in a segmented multizone trap. The quantum Fourier transform is the crucial final step in Shor's algorithm, and it acts on a register of qubits to determine the periodicity of the quantum state's amplitudes. Because only probability amplitudes are required for this task, a more efficient semiclassical version can be used, for which only single-qubit operations conditioned on measurement outcomes are required. We apply the transform to several input states of different periodicities; the results enable the location of peaks corresponding to the original periods. This demonstration incorporates the key elements of a scalable ion-trap architecture, suggesting the future capability of applying the quantum Fourier transform to a large number of qubits as required for a useful quantum factoring algorithm.

Enhanced quantum state detection efficiency through quantum information processing.

We investigate theoretically and experimentally how quantum state-detection efficiency is improved by the use of quantum information processing (QIP). Experimentally, we encode the state of one 9Be(+) ion qubit with one additional ancilla qubit. By measuring both qubits, we reduce the state-detection error in the presence of noise. The deviation from the theoretically allowed reduction is due to infidelities of the QIP operations. Applying this general scheme to more ancilla qubits suggests that error in the individual qubit measurements need not be a limit to scalable quantum computation.

Realization of quantum error correction.

Scalable quantum computation and communication require error control to protect quantum information against unavoidable noise. Quantum error correction protects information stored in two-level quantum systems (qubits) by rectifying errors with operations conditioned on the measurement outcomes. Error-correction protocols have been implemented in nuclear magnetic resonance experiments, but the inherent limitations of this technique prevent its application to quantum information processing. Here we experimentally demonstrate quantum error correction using three beryllium atomic-ion qubits confined to a linear, multi-zone trap. An encoded one-qubit state is protected against spin-flip errors by means of a three-qubit quantum error-correcting code. A primary ion qubit is prepared in an initial state, which is then encoded into an entangled state of three physical qubits (the primary and two ancilla qubits). Errors are induced simultaneously in all qubits at various rates. The encoded state is decoded back to the primary ion one-qubit state, making error information available on the ancilla ions, which are separated from the primary ion and measured. Finally, the primary qubit state is corrected on the basis of the ancillae measurement outcome. We verify error correction by comparing the corrected final state to the uncorrected state and to the initial state. In principle, the approach enables a quantum state to be maintained by means of repeated error correction, an important step towards scalable fault-tolerant quantum computation using trapped ions.

Quantum dense coding with atomic qubits.

We report the implementation of quantum dense coding on individual atomic qubits with the use of two trapped 9Be+ ions. The protocol is implemented with a complete Bell measurement that distinguishes the four operations used to encode two bits of classical information. We measure an average transmission fidelity of 0.85(1) and determine a channel capacity of 1.16(1).

Deterministic quantum teleportation of atomic qubits.

Quantum teleportation provides a means to transport quantum information efficiently from one location to another, without the physical transfer of the associated quantum-information carrier. This is achieved by using the non-local correlations of previously distributed, entangled quantum bits (qubits). Teleportation is expected to play an integral role in quantum communication and quantum computation. Previous experimental demonstrations have been implemented with optical systems that used both discrete and continuous variables, and with liquid-state nuclear magnetic resonance. Here we report unconditional teleportation of massive particle qubits using atomic (9Be+) ions confined in a segmented ion trap, which aids individual qubit addressing. We achieve an average fidelity of 78 per cent, which exceeds the fidelity of any protocol that does not use entanglement. This demonstration is also important because it incorporates most of the techniques necessary for scalable quantum information processing in an ion-trap system.

Toward Heisenberg-limited spectroscopy with multiparticle entangled states.

The precision in spectroscopy of any quantum system is fundamentally limited by the Heisenberg uncertainty relation for energy and time. For N systems, this limit requires that they be in a quantum-mechanically entangled state. We describe a scalable method of spectroscopy that can potentially take full advantage of entanglement to reach the Heisenberg limit and has the practical advantage that the spectroscopic information is transferred to states with optimal protection against readout noise. We demonstrate our method experimentally with three beryllium ions. The spectroscopic sensitivity attained is 1.45(2) times as high as that of a perfect experiment with three non-entangled particles.