BEGIN:VCALENDAR VERSION:2.0 PRODID:IEEE vTools.Events//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/New_York BEGIN:DAYLIGHT DTSTART:20230312T030000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 RRULE:FREQ=YEARLY;BYDAY=2SU;BYMONTH=3 TZNAME:EDT END:DAYLIGHT BEGIN:STANDARD DTSTART:20231105T010000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=11 TZNAME:EST END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20230811T142717Z UID:F7E1F6AC-13DD-465F-B0F6-30D41F54B84A DTSTART;TZID=America/New_York:20230719T133000 DTEND;TZID=America/New_York:20230719T150000 DESCRIPTION:Magnetic Hardening in Low-Dimensional Ferromagnets\n\nBy: Dr. J . Ping Liu\n\nDepartment of Physics\, University of Texas at Arlington\, A rlington\, TX\, USA\n\nIEEE Magnetics Society Distinguished Lecturer 2023\ n\nHow “hard” (coercive) a ferromagnet can be has been a puzzle for a century. Seven decades ago\,\nWilliam Fuller Brown offered his famous theo rem to correlate coercivity with the magnetocrystalline\nanisotropy fields in ferromagnetic materials. However\, the experimental coercivity values have been far\nbelow the calculated levels given by the theorem\, which is called Brown’s coercivity paradox.\nResearchers have attempted to solve the paradox with sustained efforts\; however\, the paradox remains\nunsol ved\, and coercivity still cannot be predicted and calculated quantitative ly by modeling.\nProgress has been made in the past 20 years in understand ing coercivity mechanisms in nanoscale low-\ndimensional ferromagnets. In fact\, ferromagnetism is a size-dependent physical phenomenon\, as\nreveal ed by theoretical studies. However\, nanoscale ferromagnetic samples with controllable size and\nshape have been available only in recent times. By adopting newly developed salt-matrix annealing\,\nsurfactant-assisted mill ing\, and improved hydrothermal and chemical solution techniques\, we used a\nbottom-up approach to produce nanostructured magnets and have successf ully synthesized\nmonodisperse ferromagnetic Fe–Pt\, Fe–Co\, and Sm– Co nanoparticles and Co nanowires with\nextraordinary properties\, which a re strongly size- and shape-dependent. A study on size-dependent\nCurie te mperature of the L10 ferromagnetic nanoparticles with sizes down to 2 nm h as experimentally\nproved a finite-size effect. A systematic study of nano wires with extremely high coercivity above their\nmagnetocrystalline aniso tropy fields has opened a door to the solution of Brown’s paradox.\n\nSp eaker(s): Dr. J. Ping Liu\, Dr. J. Ping Liu\n\nRoom: KHS 335\, Bldg: Kerr Hall\, Toronto Metropolitan University\, Toronto\, Ontario\, Canada\, Virt ual: https://events.vtools.ieee.org/m/366655 LOCATION:Room: KHS 335\, Bldg: Kerr Hall\, Toronto Metropolitan University\ , Toronto\, Ontario\, Canada\, Virtual: https://events.vtools.ieee.org/m/3 66655 ORGANIZER:ofalou@gmail.com SEQUENCE:11 SUMMARY:IEEE Magnetics Society Distinguished Lecturer 2023 URL;VALUE=URI:https://events.vtools.ieee.org/m/366655 X-ALT-DESC:Description: <br /><p><strong>Magnetic Hardening in Low-Dimensio nal Ferromagnets</strong></p>\n<p><strong>By: Dr. &nbsp\;J. Ping Liu</stro ng></p>\n<p>Department of Physics\, University of Texas at Arlington\, Arl ington\, TX\, USA</p>\n<p>IEEE Magnetics Society Distinguished Lecturer 20 23</p>\n<p><br />How &ldquo\;hard&rdquo\; (coercive) a ferromagnet can be has been a puzzle for a century. Seven decades ago\,<br />William Fuller B rown offered his famous theorem to correlate coercivity with the magnetocr ystalline<br />anisotropy fields in ferromagnetic materials. However\, the experimental coercivity values have been far<br />below the calculated le vels given by the theorem\, which is called Brown&rsquo\;s coercivity para dox.<br />Researchers have attempted to solve the paradox with sustained e fforts\; however\, the paradox remains<br />unsolved\, and coercivity stil l cannot be predicted and calculated quantitatively by modeling.<br />Prog ress has been made in the past 20 years in understanding coercivity mechan isms in nanoscale low-<br />dimensional ferromagnets. In fact\, ferromagne tism is a size-dependent physical phenomenon\, as<br />revealed by theoret ical studies. However\, nanoscale ferromagnetic samples with controllable size and<br />shape have been available only in recent times. By adopting newly developed salt-matrix annealing\,<br />surfactant-assisted milling\, and improved hydrothermal and chemical solution techniques\, we used a<br />bottom-up approach to produce nanostructured magnets and have successfu lly synthesized<br />monodisperse ferromagnetic Fe&ndash\;Pt\, Fe&ndash\;C o\, and Sm&ndash\;Co nanoparticles and Co nanowires with<br />extraordinar y properties\, which are strongly size- and shape-dependent. A study on si ze-dependent<br />Curie temperature of the L10 ferromagnetic nanoparticles with sizes down to 2 nm has experimentally<br />proved a finite-size effe ct. A systematic study of nanowires with extremely high coercivity above t heir<br />magnetocrystalline anisotropy fields has opened a door to the so lution of Brown&rsquo\;s paradox.&nbsp\;</p> END:VEVENT END:VCALENDAR