BEGIN:VCALENDAR VERSION:2.0 PRODID:IEEE vTools.Events//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/Denver BEGIN:DAYLIGHT DTSTART:20220313T030000 TZOFFSETFROM:-0700 TZOFFSETTO:-0600 RRULE:FREQ=YEARLY;BYDAY=2SU;BYMONTH=3 TZNAME:MDT END:DAYLIGHT BEGIN:STANDARD DTSTART:20221106T010000 TZOFFSETFROM:-0600 TZOFFSETTO:-0700 RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=11 TZNAME:MST END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20230216T032409Z UID:C163E77A-0E02-4459-8867-8BC93C6C73CE DTSTART;TZID=America/Denver:20221004T123000 DTEND;TZID=America/Denver:20221004T134500 DESCRIPTION:Electric manipulation of magnetization is essential for the int egration of magnetic functionalities in integrated circuits. Spin-orbit to rque (SOT)\, originating from the coupling of electron spin and orbital mo tion through spin-orbital interaction\, can effectively manipulate magneti zation. Symmetry breaking plays an important role in spintronics based on SOT. SOT requires inversion asymmetry in order to have a net effect on mag netic materials\, which is commonly realized by spatial asymmetry: a thin magnetic layer sandwiched between two dissimilar layers. This kind of stru cture restricts the SOT by mirror and rotational symmetries to have a part icular form: an “antidamping-like” component oriented in the film plan e even upon reversal of the magnetization direction. Consequently\, magnet ization perpendicular to the film plane cannot be deterministically switch ed with pure electric current. To achieve all-electric switching of perpen dicular magnetization\, it is necessary to break the mirror and rotational symmetries of the sandwiched structure. In this lecture\, I will begin wi th a basic introduction of the physical origin of SOT\, followed by the re lated symmetry analysis of a magnetic thin film in a sandwiched structure for the generation of a net SOT effect. Then\, I will introduce a new meth od—a composition gradient along the thin- film normal for breaking the i nversion symmetry—to generate bulk-like SOT [1]\, which enables a thicke r magnetic layer with high magnetic anisotropy. An overview of the methods commonly used to break mirror and rotational symmetries to realize all-el ectric switching of perpendicular magnetization will follow. I will give a detailed discussion on our methods for the realization of all-electric sw itching of perpendicular magnetization: the use of a spin source layer wit h low magnetic symmetry and low crystal symmetry\, which generates an out- of-plane SOT [2]–[4]\; interfacial 3m1 symmetry\, which induces a new “3m” spin torque [5]\; precise control of the tilting of magnetocrysta lline anisotropy easy axis [6]\; and a spin-current gradient along the cur rent direction [7].\n[1] L. Liu et al.\, “Electrical switching of perpen dicular magnetization in a single ferromagnetic layer\,” Phys. Rev. B\, vol. 101\, 220402\, June 2020.\n[2] J. Zhou et al.\, “Magnetic asymmetry induced anomalous spin-orbit torque in IrMn\,” Phys. Rev. B\, vol. 101\ , 184403\, May 2020.\n[3] J. Zhou et al.\, “Large spin-orbit torque effi ciency enhanced by magnetic structure of collinear antiferromagnet IrMn\, ” Sci. Adv.\, vol. 5\, eaau6696\, May 2019.\n[4] Q. Xie et al.\, “Fiel d-free magnetization switching induced by the unconventional spin–orbit torque from WTe2\,” APL Mater.\, vol. 9\, 051114\, May 2021.\n[5] L. Liu et al.\, “Symmetry-dependent field-free switching of perpendicular magn etization\,” Nat. Nanotech.\, vol. 16\, pp. 277-282\, January 2021.\n[6] L. Liu et al.\, “Current-induced magnetization switching in all-oxide h eterostructures\,” Nat. Nanotech.\, vol. 14\, 939-944\, September 2019.\ n[7] S. Chen et al.\, “Free field electric switching of perpendicularly magnetized thin film by spin current gradient\,” ACS Appl. Mater. Interf aces\, vol. 11\, pp. 30446-30452\, July 2019.\n\nCo-sponsored by: UCCS\n\n Speaker(s): Jingsheng Chen\, \n\nRoom: A204\, Bldg: Osborne Center for Sci ence and Engineering\, 1420 Austin Bluffs Pkwy\, Colorado Springs\, Colora do\, United States\, 80918\, Virtual: https://events.vtools.ieee.org/m/348 968 LOCATION:Room: A204\, Bldg: Osborne Center for Science and Engineering\, 14 20 Austin Bluffs Pkwy\, Colorado Springs\, Colorado\, United States\, 8091 8\, Virtual: https://events.vtools.ieee.org/m/348968 ORGANIZER:dbozhko@uccs.edu SEQUENCE:0 SUMMARY:Symmetry breaking by materials engineering for spin-orbit-torque te chnology URL;VALUE=URI:https://events.vtools.ieee.org/m/348968 X-ALT-DESC:Description: <br /><p>Electric manipulation of magnetization is essential for the integration of magnetic functionalities in integrated ci rcuits. Spin-orbit torque (SOT)\, originating from the coupling of electro n spin and orbital motion through spin-orbital interaction\, can effective ly manipulate magnetization. Symmetry breaking plays an important role in spintronics based on SOT. SOT requires inversion asymmetry in order to hav e a net effect on magnetic materials\, which is commonly realized by spati al asymmetry: a thin magnetic layer sandwiched between two dissimilar laye rs. This kind of structure restricts the SOT by mirror and rotational symm etries to have a particular form: an &ldquo\;antidamping-like&rdquo\; comp onent oriented in the film plane even upon reversal of the magnetization d irection. Consequently\, magnetization perpendicular to the film plane can not be deterministically switched with pure electric current. To achieve a ll-electric switching of perpendicular magnetization\, it is necessary to break the mirror and rotational symmetries of the sandwiched structure. In this lecture\, I will begin with a basic introduction of the physical ori gin of SOT\, followed by the related symmetry analysis of a magnetic thin film in a sandwiched structure for the generation of a net SOT effect. The n\, I will introduce a new method&mdash\;a composition gradient along the thin- film normal for breaking the inversion symmetry&mdash\;to generate b ulk-like SOT [1]\, which enables a thicker magnetic layer with high magnet ic anisotropy. An overview of the methods commonly used to break mirror an d rotational symmetries to realize all-electric switching of perpendicular magnetization will follow. I will give a detailed discussion on our metho ds for the realization of all-electric switching of perpendicular magnetiz ation: the use of a spin source layer with low magnetic symmetry and low c rystal symmetry\, which generates an out-of-plane SOT [2]&ndash\;[4]\; int erfacial 3m1 symmetry\, which induces a new &ldquo\;3m&rdquo\; spin torque [5]\; precise control of the tilting of magnetocrystalline anisotropy eas y axis [6]\; and a spin-current gradient along the current direction [7].& nbsp\;<br />[1] L. Liu et al.\, &ldquo\;Electrical switching of perpendicu lar magnetization in a single ferromagnetic layer\,&rdquo\; Phys. Rev. B\, vol. 101\, 220402\, June 2020.<br />[2] J. Zhou et al.\, &ldquo\;Magnetic asymmetry induced anomalous spin-orbit torque in IrMn\,&rdquo\; Phys. Rev . B\, vol. 101\, 184403\, May 2020.<br />[3] J. Zhou et al.\, &ldquo\;Larg e spin-orbit torque efficiency enhanced by magnetic structure of collinear antiferromagnet IrMn\,&rdquo\; Sci. Adv.\, vol. 5\, eaau6696\, May 2019.< br />[4] Q. Xie et al.\, &ldquo\;Field-free magnetization switching induce d by the unconventional spin&ndash\;orbit torque from WTe2\,&rdquo\; APL M ater.\, vol. 9\, 051114\, May 2021.<br />[5] L. Liu et al.\, &ldquo\;Symme try-dependent field-free switching of perpendicular magnetization\,&rdquo\ ; Nat. Nanotech.\, vol. 16\, pp. 277-282\, January 2021.<br />[6] L. Liu e t al.\, &ldquo\;Current-induced magnetization switching in all-oxide heter ostructures\,&rdquo\; Nat. Nanotech.\, vol. 14\, 939-944\, September 2019. <br />[7] S. Chen et al.\, &ldquo\;Free field electric switching of perpen dicularly magnetized thin film by spin current gradient\,&rdquo\; ACS Appl . Mater. Interfaces\, vol. 11\, pp. 30446-30452\, July 2019.</p> END:VEVENT END:VCALENDAR