1
|
Darwin E, Tomasello R, Shepley PM, Satchell N, Carpentieri M, Finocchio G, Hickey BJ. Antiferromagnetic interlayer exchange coupled Co 68B 32/Ir/Pt multilayers. Sci Rep 2024; 14:95. [PMID: 38168577 PMCID: PMC10761723 DOI: 10.1038/s41598-023-49976-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Accepted: 12/14/2023] [Indexed: 01/05/2024] Open
Abstract
Synthetic antiferromagnetic structures can exhibit the advantages of high velocity similarly to antiferromagnets with the additional benefit of being imaged and read-out through techniques applied to ferromagnets. Here, we explore the potential and limits of synthetic antiferromagnets to uncover ways to harness their valuable properties for applications. Two synthetic antiferromagnetic systems have been engineered and systematically investigated to provide an informed basis for creating devices with maximum potential for data storage, logic devices, and skyrmion racetrack memories. The two systems considered are (system 1) CoB/Ir/Pt of N repetitions with Ir inducing the negative coupling between the ferromagnetic layers and (system 2) two ferromagnetically coupled multilayers of CoB/Ir/Pt, coupled together antiferromagnetically with an Ir layer. From the hysteresis, it is found that system 1 shows stable antiferromagnetic interlayer exchange coupling between each magnetic layer up to N = 7. Using Kerr imaging, the two ferromagnetic multilayers in system 2 are shown to undergo separate maze-like switches during hysteresis. Both systems are also studied as a function of temperature and show different behaviors. Micromagnetic simulations predict that in both systems the skyrmion Hall angle is suppressed with the skyrmion velocity five times higher in system 1 than system 2.
Collapse
Affiliation(s)
- Emily Darwin
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
- Department of Electrical and Information Engineering, Politecnico Di Bari, Via E. Orabona 4, 70125, Bari, Italy
| | - Riccardo Tomasello
- Department of Electrical and Information Engineering, Politecnico Di Bari, Via E. Orabona 4, 70125, Bari, Italy
| | - Philippa M Shepley
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Nathan Satchell
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
- Department of Physics, Texas State University, San Marcos, TX, 78666, USA
| | - Mario Carpentieri
- Department of Electrical and Information Engineering, Politecnico Di Bari, Via E. Orabona 4, 70125, Bari, Italy
| | - Giovanni Finocchio
- Department of Mathematical and Computer Sciences, Physical Sciences and Earth Sciences, University of Messina, 98166, Messina, Italy.
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
2
|
Cubukcu M, Pöllath S, Tacchi S, Stacey A, Darwin E, Freeman CWF, Barton C, Hickey BJ, Marrows CH, Carlotti G, Back CH, Kazakova O. Manipulation of Magnetic Skyrmion Density in Continuous Ir/Co/Pt Multilayers. Micromachines (Basel) 2022; 13:1911. [PMID: 36363931 PMCID: PMC9693305 DOI: 10.3390/mi13111911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 10/27/2022] [Accepted: 11/02/2022] [Indexed: 06/16/2023]
Abstract
We show that magnetic skyrmions can be stabilised at room temperature in continuous [Ir/Co/Pt]5 multilayers on SiO2/Si substrates without the prior application of electric current or magnetic field. While decreasing the Co thickness, a transition of the magnetic domain patterns from worm-like state to separated stripes is observed. The skyrmions are clearly imaged in both states using magnetic force microscopy. The density of skyrmions can be significantly enhanced after applying the "in-plane field procedure". Our results provide means to manipulate magnetic skyrmion density, further allowing for the optimised engineering of skyrmion-based devices.
Collapse
Affiliation(s)
- M. Cubukcu
- National Physical Laboratory, Teddington TW11 0LW, UK
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UK
| | - S. Pöllath
- Institut für Experimentelle Physik, Universität Regensburg, D-93040 Regensburg, Germany
| | - S. Tacchi
- Istituto Officina dei Materiali del CNR (CNR-IOM), Sede Secondaria di Perugia, c/o Dipartimento di Fisica e Geologia, Università di Perugia, I-06123 Perugia, Italy
| | - A. Stacey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - E. Darwin
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - C. W. F. Freeman
- National Physical Laboratory, Teddington TW11 0LW, UK
- London Centre for Nanotechnology, University College London, 17-19 Gordon Street, London WC1H 0AH, UK
| | - C. Barton
- National Physical Laboratory, Teddington TW11 0LW, UK
| | - B. J. Hickey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - C. H. Marrows
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - G. Carlotti
- Dipartimento di Fisica e Geologia, Università di Perugia, Via Pascoli, I-06123 Perugia, Italy
| | - C. H. Back
- Physik-Department, Technical University Munich, 85748 Garching, Germany
| | - O. Kazakova
- National Physical Laboratory, Teddington TW11 0LW, UK
| |
Collapse
|
3
|
Stefanou G, Menges F, Boehm B, Moran KA, Adams J, Ali M, Rosamond MC, Gotsmann B, Allenspach R, Burnell G, Hickey BJ. Scanning Thermal Microscopy and Ballistic Phonon Transport in Lateral Spin Valves. Phys Rev Lett 2021; 127:035901. [PMID: 34328759 DOI: 10.1103/physrevlett.127.035901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 04/13/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Abstract
Using scanning thermal microscopy, we have mapped the spatial distribution of temperatures in an operating nanoscale device formed from a magnetic injector, an Ag connecting wire, and a magnetic detector. An analytical model explained the thermal diffusion over the measured temperature range (2-300 K) and injector-detector separation (400-3000 nm). The characteristic diffusion lengths of the Peltier and Joule heat differ remarkably below 60 K, a fact that can be explained by the onset of ballistic phonon heat transfer in the substrate.
Collapse
Affiliation(s)
- G Stefanou
- School of Physics and Astronomy, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - F Menges
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - B Boehm
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - K A Moran
- School of Physics and Astronomy, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - J Adams
- School of Physics and Astronomy, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - M Ali
- School of Physics and Astronomy, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - M C Rosamond
- School of Electronics and Electrical Engineering, University of Leeds, LS2 9JT Leeds, United Kingdom
| | - B Gotsmann
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - R Allenspach
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - G Burnell
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, LS2 9JT Leeds, United Kingdom
| |
Collapse
|
4
|
Satchell N, Mitchell T, Shepley PM, Darwin E, Hickey BJ, Burnell G. Pt and CoB trilayer Josephson [Formula: see text] junctions with perpendicular magnetic anisotropy. Sci Rep 2021; 11:11173. [PMID: 34045523 PMCID: PMC8159980 DOI: 10.1038/s41598-021-90432-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 04/05/2021] [Indexed: 11/13/2022] Open
Abstract
We report on the electrical transport properties of Nb based Josephson junctions with Pt/Co[Formula: see text]B[Formula: see text]/Pt ferromagnetic barriers. The barriers exhibit perpendicular magnetic anisotropy, which has the main advantage for potential applications over magnetisation in-plane systems of not affecting the Fraunhofer response of the junction. In addition, we report that there is no magnetic dead layer at the Pt/Co[Formula: see text]B[Formula: see text] interfaces, allowing us to study barriers with ultra-thin Co[Formula: see text]B[Formula: see text]. In the junctions, we observe that the magnitude of the critical current oscillates with increasing thickness of the Co[Formula: see text]B[Formula: see text] strong ferromagnetic alloy layer. The oscillations are attributed to the ground state phase difference across the junctions being modified from zero to [Formula: see text]. The multiple oscillations in the thickness range [Formula: see text] nm suggests that we have access to the first zero-[Formula: see text] and [Formula: see text]-zero phase transitions. Our results fuel the development of low-temperature memory devices based on ferromagnetic Josephson junctions.
Collapse
Affiliation(s)
- N. Satchell
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| | - T. Mitchell
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| | - P. M. Shepley
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| | - E. Darwin
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| | - B. J. Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| | - G. Burnell
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT UK
| |
Collapse
|
5
|
Moorsom T, Rogers M, Scivetti I, Bandaru S, Teobaldi G, Valvidares M, Flokstra M, Lee S, Stewart R, Prokscha T, Gargiani P, Alosaimi N, Stefanou G, Ali M, Al Ma’Mari F, Burnell G, Hickey BJ, Cespedes O. Reversible spin storage in metal oxide-fullerene heterojunctions. Sci Adv 2020; 6:eaax1085. [PMID: 32219155 PMCID: PMC7083605 DOI: 10.1126/sciadv.aax1085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
We show that hybrid MnOx/C60 heterojunctions can be used to design a storage device for spin-polarized charge: a spin capacitor. Hybridization at the carbon-metal oxide interface leads to spin-polarized charge trapping after an applied voltage or photocurrent. Strong electronic structure changes, including a 1-eV energy shift and spin polarization in the C60 lowest unoccupied molecular orbital, are then revealed by x-ray absorption spectroscopy, in agreement with density functional theory simulations. Muon spin spectroscopy measurements give further independent evidence of local spin ordering and magnetic moments optically/electronically stored at the heterojunctions. These spin-polarized states dissipate when shorting the electrodes. The spin storage decay time is controlled by magnetic ordering at the interface, leading to coherence times of seconds to hours even at room temperature.
Collapse
Affiliation(s)
- T. Moorsom
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - M. Rogers
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - I. Scivetti
- Stephenson Institute for Renewable Energy, Department of Chemistry, University of Liverpool, Liverpool L69 3BX, England
| | - S. Bandaru
- Beijing Computational Science Research Centre, 100193 Beijing, China
| | - G. Teobaldi
- Stephenson Institute for Renewable Energy, Department of Chemistry, University of Liverpool, Liverpool L69 3BX, England
- Beijing Computational Science Research Centre, 100193 Beijing, China
| | - M. Valvidares
- ALBA Synchrotron Light Source, E-08290 Barcelona, Spain
| | - M. Flokstra
- School of Physics and Astronomy, SUPA, University of St Andrews, St Andrews KY16 9SS, UK
| | - S. Lee
- School of Physics and Astronomy, SUPA, University of St Andrews, St Andrews KY16 9SS, UK
| | - R. Stewart
- School of Physics and Astronomy, SUPA, University of St Andrews, St Andrews KY16 9SS, UK
| | - T. Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - P. Gargiani
- ALBA Synchrotron Light Source, E-08290 Barcelona, Spain
| | - N. Alosaimi
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - G. Stefanou
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - M. Ali
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - F. Al Ma’Mari
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
- Department of Physics, Sultan Qaboos University, P.O. Box 36, 123 Muscat, Oman
| | - G. Burnell
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - B. J. Hickey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | - O. Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| |
Collapse
|
6
|
Wheeler MC, Ma'Mari FA, Rogers M, Gonçalves FJ, Moorsom T, Brataas A, Stamps R, Ali M, Burnell G, Hickey BJ, Cespedes O. Optical conversion of pure spin currents in hybrid molecular devices. Nat Commun 2017; 8:926. [PMID: 29030558 PMCID: PMC5640639 DOI: 10.1038/s41467-017-01034-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 08/14/2017] [Indexed: 11/20/2022] Open
Abstract
Carbon-based molecules offer unparalleled potential for THz and optical devices controlled by pure spin currents: a low-dissipation flow of electronic spins with no net charge displacement. However, the research so far has been focused on the electrical conversion of the spin imbalance, where molecular materials are used to mimic their crystalline counterparts. Here, we use spin currents to access the molecular dynamics and optical properties of a fullerene layer. The spin mixing conductance across Py/C60 interfaces is increased by 10% (5 × 1018 m-2) under optical irradiation. Measurements show up to a 30% higher light absorbance and a factor of 2 larger photoemission during spin pumping. We also observe a 0.15 THz slowdown and a narrowing of the vibrational peaks. The effects are attributed to changes in the non-radiative damping and energy transfer. This opens new research paths in hybrid magneto-molecular optoelectronics, and the optical detection of spin physics in these materials.Carbon-based molecules could prove useful in terahertz and optical devices controlled by pure spin currents. Here, conversely, the authors use spin currents to probe molecular dynamics and enhance the optical response of a fullerene layer, enabling hybrid magneto-molecular optoelectronic devices.
Collapse
Affiliation(s)
- May C Wheeler
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Fatma Al Ma'Mari
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
- Department of Physics, Sultan Qaboos University, PO Box 36, Muscat, 123, Oman
| | - Matthew Rogers
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | | | - Timothy Moorsom
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Arne Brataas
- Department of Physics, Norwegian University of Science and Technology, Trondheim, NO, 7491, Norway
| | - Robert Stamps
- School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Mannan Ali
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Gavin Burnell
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Oscar Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
7
|
Mitra A, Cespedes O, Ramasse Q, Ali M, Marmion S, Ward M, Brydson RMD, Kinane CJ, Cooper JFK, Langridge S, Hickey BJ. Interfacial Origin of the Magnetisation Suppression of Thin Film Yttrium Iron Garnet. Sci Rep 2017; 7:11774. [PMID: 28924173 PMCID: PMC5603596 DOI: 10.1038/s41598-017-10281-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 07/18/2017] [Indexed: 11/10/2022] Open
Abstract
Yttrium iron garnet has a very high Verdet constant, is transparent in the infrared and is an insulating ferrimagnet leading to its use in optical and magneto-optical applications. Its high Q-factor has been exploited to make resonators and filters in microwave devices, but it also has the lowest magnetic damping of any known material. In this article we describe the structural and magnetic properties of single crystal thin-film YIG where the temperature dependence of the magnetisation reveals a decrease in the low temperature region. In order to understand this complex material we bring a large number of structural and magnetic techniques to bear on the same samples. Through a comprehensive analysis we show that at the substrate -YIG interface, an interdiffusion zone of only 4–6 nm exists. Due to the interdiffusion of Y from the YIG and Gd from the substrate, an addition magnetic layer is formed at the interface whose properties are crucially important in samples with a thickness of YIG less than 200 nm.
Collapse
Affiliation(s)
- A Mitra
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - O Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Q Ramasse
- SuperSTEM Laboratory, SciTech Daresbury Campus, Keckwick Lane, Daresbury, WA4 4AD, UK
| | - M Ali
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - S Marmion
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - M Ward
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - R M D Brydson
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - C J Kinane
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - J F K Cooper
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - S Langridge
- Rutherford Appleton Laboratory, ISIS, Science and Technology Facilities Council, Didcot, OX11 0QX, Oxon, UK
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
8
|
Al Ma'Mari F, Rogers M, Alghamdi S, Moorsom T, Lee S, Prokscha T, Luetkens H, Valvidares M, Teobaldi G, Flokstra M, Stewart R, Gargiani P, Ali M, Burnell G, Hickey BJ, Cespedes O. Emergent magnetism at transition-metal-nanocarbon interfaces. Proc Natl Acad Sci U S A 2017; 114:5583-5588. [PMID: 28507160 PMCID: PMC5465901 DOI: 10.1073/pnas.1620216114] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Charge transfer at metallo-molecular interfaces may be used to design multifunctional hybrids with an emergent magnetization that may offer an eco-friendly and tunable alternative to conventional magnets and devices. Here, we investigate the origin of the magnetism arising at these interfaces by using different techniques to probe 3d and 5d metal films such as Sc, Mn, Cu, and Pt in contact with fullerenes and rf-sputtered carbon layers. These systems exhibit small anisotropy and coercivity together with a high Curie point. Low-energy muon spin spectroscopy in Cu and Sc-C60 multilayers show a quick spin depolarization and oscillations attributed to nonuniform local magnetic fields close to the metallo-carbon interface. The hybridization state of the carbon layers plays a crucial role, and we observe an increased magnetization as sp3 orbitals are annealed into sp2-π graphitic states in sputtered carbon/copper multilayers. X-ray magnetic circular dichroism (XMCD) measurements at the carbon K edge of C60 layers in contact with Sc films show spin polarization in the lowest unoccupied molecular orbital (LUMO) and higher π*-molecular levels, whereas the dichroism in the σ*-resonances is small or nonexistent. These results support the idea of an interaction mediated via charge transfer from the metal and dz-π hybridization. Thin-film carbon-based magnets may allow for the manipulation of spin ordering at metallic surfaces using electrooptical signals, with potential applications in computing, sensors, and other multifunctional magnetic devices.
Collapse
Affiliation(s)
- Fatma Al Ma'Mari
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
- Department of Physics, Sultan Qaboos University, 123 Muscat, Oman
| | - Matthew Rogers
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Shoug Alghamdi
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Timothy Moorsom
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Stephen Lee
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - Thomas Prokscha
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | - Hubertus Luetkens
- Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, 5232 Villigen, Switzerland
| | | | - Gilberto Teobaldi
- Stephenson Institute for Renewable Energy, Department of Chemistry, University of Liverpool, Liverpool L69 3BX, United Kingdom
- Beijing Computational Science Research Centre, Beijing 100193 China
| | - Machiel Flokstra
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | - Rhea Stewart
- School of Physics and Astronomy, Scottish Universities Physics Alliance, University of St. Andrews, St. Andrews KY16 9SS, United Kingdom
| | | | - Mannan Ali
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Gavin Burnell
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Oscar Cespedes
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom;
| |
Collapse
|
9
|
Temple RC, McLaren M, Brydson RMD, Hickey BJ, Marrows CH. Long spin lifetime and large barrier polarisation in single electron transport through a CoFe nanoparticle. Sci Rep 2016; 6:28296. [PMID: 27329575 PMCID: PMC4916452 DOI: 10.1038/srep28296] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 05/25/2016] [Indexed: 11/09/2022] Open
Abstract
We have investigated single electron spin transport in individual single crystal bcc Co30Fe70 nanoparticles using scanning tunnelling microscopy with a standard tungsten tip. Particles were deposited using a gas-aggregation nanoparticle source and individually addressed as asymmetric double tunnel junctions with both a vacuum and a MgO tunnel barrier. Spectroscopy measurements on the particles show a Coulomb staircase that is correlated with the measured particle size. Field emission tunnelling effects are incorporated into standard single electron theory to model the data. This formalism allows spin-dependent parameters to be determined even though the tip is not spin-polarised. The barrier spin polarisation is very high, in excess of 84%. By variation of the resistance, several orders of magnitude of the system timescale are probed, enabling us to determine the spin relaxation time on the island. It is found to be close to 10 μs, a value much longer than previously reported.
Collapse
Affiliation(s)
- R C Temple
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - M McLaren
- Institute for Materials Research, School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - R M D Brydson
- Institute for Materials Research, School of Chemical and Process Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - B J Hickey
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - C H Marrows
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| |
Collapse
|
10
|
Saerbeck T, Loh N, Lott D, Toperverg BP, Mulders AM, Fraile Rodríguez A, Freeland JW, Ali M, Hickey BJ, Stampfl APJ, Klose F, Stamps RL. Spatial fluctuations of loose spin coupling in CuMn/Co multilayers. Phys Rev Lett 2011; 107:127201. [PMID: 22026792 DOI: 10.1103/physrevlett.107.127201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Indexed: 05/31/2023]
Abstract
A detailed investigation of magnetic impurity-mediated interlayer exchange coupling observed in Cu(0.94)Mn(0.06)/Co multilayers using polarized neutron reflectometry and magnetic x-ray techniques is reported. Excellent descriptions of temperature and magnetic field dependent biquadratic coupling are obtained using a variant of the loose spin model that takes into account the distribution of the impurity Mn ions in three dimensions. Positional disorder of the magnetic impurities is shown to enhance biquadratic coupling via a new contribution J(2)(fluct), leading to a temperature dependent canting of magnetic domains in the multilayer. These results provide measurable effects on RKKY coupling associated with the distribution of impurities within planes parallel to the interfaces.
Collapse
Affiliation(s)
- T Saerbeck
- School of Physics, University of Western Australia, Crawley, WA6009, Australia.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
Conventional microelectronics exploits only the charge degree of freedom of the electron. Bringing the spin degree of freedom to bear on sensing, radio frequency, memory and logic applications opens up new possibilities for 'more than Moore' devices incorporating magnetic components that can couple to an external field, store a bit of data or represent a Boolean state. Moreover, the electron spin is an archetypal two-state quantum system that is an excellent candidate for a solid-state realization of a qubit.
Collapse
Affiliation(s)
- C H Marrows
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK.
| | | |
Collapse
|
12
|
Seemann KM, Mokrousov Y, Aziz A, Miguel J, Kronast F, Kuch W, Blamire MG, Hindmarch AT, Hickey BJ, Souza I, Marrows CH. Spin-orbit strength driven crossover between intrinsic and extrinsic mechanisms of the anomalous hall effect in the epitaxial L1{0}-ordered ferromagnets FePd and FePt. Phys Rev Lett 2010; 104:076402. [PMID: 20366900 DOI: 10.1103/physrevlett.104.076402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2009] [Indexed: 05/29/2023]
Abstract
We determine the composition of intrinsic as well as extrinsic contributions to the anomalous Hall effect (AHE) in the isoelectronic L1_{0} FePd and FePt alloys. We show that the AHE signal in our 30 nm thick epitaxially deposited films of FePd is mainly due to an extrinsic side jump, while in the epitaxial FePt films of the same thickness and degree of order the intrinsic contribution is dominating over the extrinsic mechanisms of the AHE. We relate this crossover to the difference in spin-orbit strength of Pt and Pd atoms and suggest that this phenomenon can be used for tuning the origins of the AHE in complex alloys.
Collapse
Affiliation(s)
- K M Seemann
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Aziz A, Wessely OP, Ali M, Edwards DM, Marrows CH, Hickey BJ, Blamire MG. Nonlinear giant magnetoresistance in dual spin valves. Phys Rev Lett 2009; 103:237203. [PMID: 20366169 DOI: 10.1103/physrevlett.103.237203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2009] [Indexed: 05/29/2023]
Abstract
Giant magnetoresistance (GMR) arises from differential scattering of the majority and minority spin electrons by a ferromagnet (FM) so that the resistance of a heterostructure depends on the relative magnetic orientation of the FM layers within it separated by nonmagnetic spacers. Here, we show that highly nonequilibrium spin accumulation in metallic heterostructures results in a current-dependent nonlinear GMR which is not predicted within the present understanding of GMR. The behavior can be explained by allowing the scattering asymmetries in an ultrathin FM layer to be current dependent.
Collapse
Affiliation(s)
- A Aziz
- Department of Materials Science, Cambridge University, Pembroke Street, Cambridge CB2 3QZ, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
14
|
Baltz V, Naylor AD, Seemann KM, Elder W, Sheen S, Westerholt K, Zabel H, Burnell G, Marrows CH, Hickey BJ. Conductance features in point contact Andreev reflection spectra. J Phys Condens Matter 2009; 21:095701. [PMID: 21817404 DOI: 10.1088/0953-8984/21/9/095701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Point contact Andreev reflection (PCAR) spectroscopy is a common technique for determining the spin polarization of a ferromagnetic sample. The polarization is extracted by measuring the bias dependence of the conductance of a metallic/superconducting point contact. Under ideal conditions, the conductance is dominated by Andreev reflection and the Blonder-Tinkham-Klapwijk (BTK) model can be used to extract a value for the polarization. However, PCAR spectra often exhibit unwanted features in the conductance that cannot be appropriately modelled with the BTK theory. In this paper we isolate some of these unwanted features and show that any further extraction of the spin polarization from these non-ideal spectra proves unreliable. Understanding the origin of these features provides an objective criterion for rejection of PCAR spectra unsuitable for fitting with the modified BTK model.
Collapse
Affiliation(s)
- V Baltz
- School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, UK
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Wu MC, Aziz A, Witt JDS, Hickey MC, Ali M, Marrows CH, Hickey BJ, Blamire MG. Structural and functional analysis of nanopillar spin electronic devices fabricated by 3D focused ion beam lithography. Nanotechnology 2008; 19:485305. [PMID: 21836299 DOI: 10.1088/0957-4484/19/48/485305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We discuss the fabrication of nanopillar spin electronic devices from metal multilayered heterostructures, utilizing a novel three-dimensional focused ion beam lithography process. Finite element simulation was performed to optimize the geometry of the nanopillar device and to demonstrate that current flow is perpendicular to the plane within the active region of the device. Clear zero-field current induced magnetization switching is observed in our nanopillar devices at room temperature.
Collapse
Affiliation(s)
- M C Wu
- Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, UK
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Blamire MG, Ali M, Leung CW, Marrows CH, Hickey BJ. Exchange bias and blocking temperature in Co/FeMn/CuNi trilayers. Phys Rev Lett 2007; 98:217202. [PMID: 17677802 DOI: 10.1103/physrevlett.98.217202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Indexed: 05/16/2023]
Abstract
Aspects of exchange bias between antiferromagnets and ferromagnets remain unclear despite recent research. An outstanding issue is the relationship between exchange bias and enhanced coercivity in the ferromagnetic layer. This Letter reports the unexpected finding that a substantial exchange bias can be generated between an antiferromagnet (FeMn) with a higher ordering temperature than that of the ferromagnet (CuNi). We interpret the result in terms of a temperature-dependent competition between interfacial exchange and antiferromagnet anisotropy energies. Crossover of these energies during cooling is responsible for the onset of exchange bias at the blocking temperature.
Collapse
Affiliation(s)
- M G Blamire
- Department of Materials Science, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ, United Kingdom
| | | | | | | | | |
Collapse
|
17
|
Hindmarch AT, Hickey BJ. Direct experimental evidence for the Ruderman-Kittel-Kasuya-Yosida interaction in rare-earth metals. Phys Rev Lett 2003; 91:116601. [PMID: 14525448 DOI: 10.1103/physrevlett.91.116601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2003] [Indexed: 05/24/2023]
Abstract
We show that the ferromagnetic heavy rare-earth (RE) metals show a transport spin polarization at the Fermi level in the majority spin, whereas in ferromagnetic light rare earths it is in the minority spin. The sign of the polarization is in agreement with what is expected due to the Ruderman-Kittel-Kasuya-Yosida (RKKY) coupling formalism. We show that magnetotransport measurements on magnetic multilayer samples containing magnetic REs provide a unique opportunity to verify the RKKY coupling scheme in pure rare-earth metals, allowing us to probe both the sign and temperature dependence of the spin-density oscillation.
Collapse
Affiliation(s)
- A T Hindmarch
- Department of Physics & Astronomy, University of Leeds, Leeds, LS2 9JT United Kingdom.
| | | |
Collapse
|
18
|
Steadman P, Ali M, Hindmarch AT, Marrows CH, Hickey BJ, Langridge S, Dalgliesh RM, Foster S. Exchange bias in spin-engineered double superlattices. Phys Rev Lett 2002; 89:077201. [PMID: 12190551 DOI: 10.1103/physrevlett.89.077201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2002] [Indexed: 05/23/2023]
Abstract
Exchange bias has been observed in sputtered magnetic double superlattices which consist of a ferromagnetically coupled superlattice grown on an antiferromagnetically (AF) coupled superlattice. This system exhibits a parallel domain wall, a spin flop transition, and exchange bias when the anisotropy is large in the AF block. This work shows that neither the domain wall nor the spin flop are directly related to exchange bias but that the anisotropy is essential.
Collapse
Affiliation(s)
- P Steadman
- Department of Physics and Astronomy, E. C. Stoner Laboratory, University of Leeds, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Dekadjevi DT, Ryan PA, Hickey BJ, Fulthorpe BD, Tanner BK. Experimental evidence for electron channeling in Fe /Aau (100) superlattices. Phys Rev Lett 2001; 86:5787-5790. [PMID: 11415358 DOI: 10.1103/physrevlett.86.5787] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2000] [Indexed: 05/23/2023]
Abstract
We present transport and structural data from epitaxial (100) and (111) Au/Fe superlattices grown by molecular beam epitaxy. From their analysis, we conclude that an electron channeling mechanism, due to strong specular reflection of the minority spin carrier at the Au/Fe interfaces, is responsible for the high conductivity in the (100) superlattices.
Collapse
Affiliation(s)
- D T Dekadjevi
- Department of Physics and Astronomy, E. C. Stoner Laboratory, University of Leeds, Leeds LS2 9JT, United Kingdom
| | | | | | | | | |
Collapse
|
20
|
Langridge S, Schmalian J, Marrows CH, Dekadjevi DT, Hickey BJ. Quantification of magnetic domain disorder and correlations in antiferromagnetically coupled multilayers by neutron reflectometry. Phys Rev Lett 2000; 85:4964-4967. [PMID: 11102162 DOI: 10.1103/physrevlett.85.4964] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/1999] [Indexed: 05/23/2023]
Abstract
The in-plane correlation lengths and angular dispersion of magnetic domains in a transition metal multilayer have been studied using off-specular neutron reflectometry techniques. A theoretical framework considering both structural and magnetic disorder has been developed, quantitatively connecting the observed scattering to the in-plane correlation length and the dispersion of the local magnetization vector about the mean macroscopic direction. The antiferromagnetic domain structure is highly vertically correlated throughout the multilayer. We are easily able to relate the neutron determined magnetic domain dispersion to magnetization and magnetoresistance experiments.
Collapse
Affiliation(s)
- S Langridge
- Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | | | | | | | | |
Collapse
|
21
|
Hickey BJ, Morgan GJ. The density of states and spectral function in amorphous Si obtained using the equation of motion method in k-space. ACTA ACUST UNITED AC 2000. [DOI: 10.1088/0022-3719/19/31/014] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
22
|
|
23
|
|
24
|
Bozec D, Howson MA, Hickey BJ, Shatz S, Wiser N, Tsymbal EY, Pettifor DG. Mean free path effects on the current perpendicular to the plane magnetoresistance of magnetic multilayers. Phys Rev Lett 2000; 85:1314-1317. [PMID: 10991540 DOI: 10.1103/physrevlett.85.1314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/1999] [Indexed: 05/23/2023]
Abstract
We have carried out an experimental and theoretical study of the magnetoresistance MR(H) in the CPP (current perpendicular to the planes) mode for two types of magnetic multilayers that differ only in the ordering of the magnetic layers: [Co(10 A)/Cu(200 A)/Co(60 A)/Cu(200 A)](N) and [Co(10 A)/Cu(200 A)](N)[Co(60 A)/Cu(200 A)](N). The series resistor model predicts that in the CPP mode MR(H) is independent of the ordering of the layers. Nevertheless, the measured MR(H) curves were found to be completely different for the two cases. Calculations based on a realistic band structure and the Kubo formula show that the results are a consequence of a long mean free path.
Collapse
Affiliation(s)
- D Bozec
- Department of Physics and Astronomy, E. C. Stoner Laboratory, University of Leeds, Leeds LS2 9JT, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
25
|
Hickey BJ, Howson MA, Greig D, Wiser N. Enhanced magnetic anisotropy energy density for superparamagnetic particles of cobalt. Phys Rev B Condens Matter 1996; 53:32-33. [PMID: 9981933 DOI: 10.1103/physrevb.53.32] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
26
|
Mayeya FM, Hickey BJ, Howson MA. Free-electron-like Hall effect and deviations from free-electron behavior in Ca-Al amorphous alloys. Phys Rev B Condens Matter 1995; 51:15567-15568. [PMID: 9978518 DOI: 10.1103/physrevb.51.15567] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
27
|
Hickey BJ, Howson MA, Musa SO, Wiser N. Giant magnetoresistance for superparamagnetic particles: Melt-spun granular CuCo. Phys Rev B Condens Matter 1995; 51:667-669. [PMID: 9977144 DOI: 10.1103/physrevb.51.667] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
28
|
Howson MA, Hickey BJ, Xu J, Greig D, Rhodes P, Wiser N. Magnetization of (111)-oriented MBE-grown Co/Cu magnetic multilayers. Phys Rev B Condens Matter 1994; 49:9560-9566. [PMID: 10009754 DOI: 10.1103/physrevb.49.9560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
29
|
Howson MA, Hickey BJ, Xu J, Greig D, Wiser N. Oscillations in the exchange coupling for (111)-oriented Co/Cu magnetic multilayers grown by molecular-beam epitaxy. Phys Rev B Condens Matter 1993; 48:1322-1324. [PMID: 10008004 DOI: 10.1103/physrevb.48.1322] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
30
|
Hall MJ, Hickey BJ, Howson MA, Walker MJ, Xu J, Greig D, Wiser N. Magnetoresistance of Co/Cu superlattices grown by molecular beam epitaxy. Phys Rev B Condens Matter 1993; 47:12785-12793. [PMID: 10005475 DOI: 10.1103/physrevb.47.12785] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
31
|
Hickey BJ. Introductory solid state physicsby H. P. Myers. Acta Crystallogr A 1993. [DOI: 10.1107/s0108767392007566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
32
|
Burr JN, Bruce NA, Hickey BJ, Holender JM, Morgan GJ. Electronic properties of amorphous systems describable by a pseudopotential with applications to amorphous Si. Phys Rev B Condens Matter 1992; 45:1116-1125. [PMID: 10001585 DOI: 10.1103/physrevb.45.1116] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
33
|
Howson MA, Hickey BJ, Morgan GJ. Quantum interference effects and the magnitude of the resistivity and thermopower of Ca-Al metallic glasses. Phys Rev B Condens Matter 1988; 38:5267-5271. [PMID: 9946961 DOI: 10.1103/physrevb.38.5267] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
34
|
Hickey BJ, Greig D, Howson MA. Localization, Coulomb interaction, and spin-orbit scattering in amorphous Cu-Ti-Au alloys. Phys Rev B Condens Matter 1987; 36:3074-3078. [PMID: 9943215 DOI: 10.1103/physrevb.36.3074] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
|
35
|
Blunt JW, Ditzel EJ, Hartshorn MP, Hickey BJ, Johnstone PK, Munro MHG, Robinson WT. The acid-catalysed rearrangement of (8R, l3R)-8,17-epoxylabd-14-en-13-ol; X-ray structure analysis of a tetracyclic ether product. Aust J Chem 1981. [DOI: 10.1071/ch9812475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The structure and
stereochemistry of the tetracyclic ether (5) formed in
the acid-catalysed rearrangement of (8R,13R)-8,17-epoxylabd-14-en-13-ol (3) is
presented. Although vinyl group participation was involved it was by a
non-biosynthetic route.
Collapse
|