Spintronics

Spintronics is the study of the intrinsic spin of the electron and its associated magnetic moment, in addition to its fundamental electronic charge, in solid-state devices.
Spintronics differs from the older magnetoelectronics, in that spins are manipulated by both magnetic and electrical fields.

  • A Material with Promising Properties

    Picture of a hybrid particle taken by a transmission electron microscope. Pictured are the inorganic (dark) and organic (light) lamellas that the particle is made of, as well as the tubular shapes (the low-contrast area in the middle). Through vaporisation with Europium, the hybrid stage can be transformed into pure EuO. Copyright: University of Konstanz

    Konstanz scientist synthesises an important ferromagnetic semiconductor. The Collaborative Research Centre CRC 1214 at the University of Konstanz has developed a method for synthesising Europium (II) oxide nanoparticles - a ferromagnetic semiconductor that is relevant for data storage and data transport. Ferromagnetic semiconductors have attracted increasing attention over the last decade. Their properties make them promising functional materials that can be used in the field of spin-based electronics (spintronics). Spintronics is of crucial importance for the storage and transport of information.

  • A new spin on electronics

    The spin of electrons transports information in this conducting layer between two isolators. Image: Christoph Hohmann / NIM

    Interface between insulators enables information transport by spin.
    Modern computer technology is based on the transport of electric charge in semiconductors. But this technology’s potential will be reaching its limits in the near future, since the components deployed cannot be miniaturized further. But, there is another option: using an electron’s spin, instead of its charge, to transmit information. A team of scientists from Munich and Kyoto is now demonstrating how this works.

  • Antiferromagnets Prove their Potential for Spin-Based Information Technology

    Crystal structure of Mn2Au with antiferromagnetically ordered magnetic moments  Ill./©: Libor Šmejkal, JGU

    Physicists at Mainz University demonstrate technologically feasible read-out and writing of digital information in antiferromagnets / Basic principle for ultrafast and stable magnetic memory. Within the emerging field of spin-based electronics, or spintronics, information is typically defined by the orientation of the magnetization of ferromagnets. Researchers have recently been also interested in the utilization of antiferromagnets, which are materials without macroscopic magnetization but with a staggered orientation of their microscopic magnetic moments. Here the information is encoded in the direction of the modulation of the magnetic moments, the so-called Néel vector.

  • Breakthrough in spintronics

    Bismuthene film through the scanning tunnelling microscope. The honeycomb structure of the material (blue) is visible. A conducting edge channel (white) forms at the edge of the insulating film. Abbildung: Felix Reis

    It's ultra-thin, electrically conducting at the edge and highly insulating within – and all that at room temperature: Physicists from the University of Würzburg have developed a promising new material. The material class of topological insulators is presently the focus of international solids research. These materials are electrically insulating within, because the electrons maintain strong bonds to the atoms. At their surfaces, however, they are conductive due to quantum effects. 

  • Construction Set of Magnon Logic Extended: Magnon Spin Currents Controlled Via Spin Valve Structure

    Depending on the magnetic configuration of the spin valve, the electrical signal is transmitted (bottom) or suppressed (top). ill./©: Joel Cramer

    Magnon spintronics employs magnons instead of electrical charges for information processing. In the emerging field of magnon spintronics, researchers investigate the possibility to transport and process information by means of so-called magnon spin currents. In contrast to electrical currents, on which todays information technology is based, magnon spin currents do not conduct electrical charges but magnetic momenta.

  • Eine Mini-Antenne für die Erzeugung von hochfrequenten Spinwellen

    Eine Mini Antenne für die Erzeugung von hochfrequenten Spinwellen | Das Zentrum eines magnetischen Wirbels sendet unter hochfrequenten magnetischen Wechselfeldern Spinwellen mit sehr kurzen Wellenlängen aus. Abbildung: HZDR

    Im Zuge der rasant fortschreitenden Miniaturisierung steht die Datenverarbeitung mit Hilfe elektrischer Ströme vor zum Teil unlösbaren Herausforderungen. Eine vielversprechende Alternative für den Informationstransport in noch kompakteren Chips sind magnetische Spinwellen. Wissenschaftlern des Helmholtz-Zentrums Dresden-Rossendorf (HZDR) ist es nun bei einer internationalen Zusammenarbeit gelungen, Spinwellen mit extrem kurzen Wellenlängen im Nanometer-Bereich – eine entscheidende Eigenschaft für die spätere Anwendung – gezielt zu erzeugen.

  • Eine neue Art von Quanten-Bits: Elektronenlöcher

    Eine neue Art von Quanten Bits Elektronenlöcher picture 1 | Das Team vom Lehrstuhl für Festkörperphysik arbeitet mit winzigen Strukturen. Die Quantenpunkte, die die Forscher um Andreas Wieck erzeugen, sind gerade einmal 30 Nanometer breit. Photo: RUB, Marquard

    Ein Forscherteam aus Deutschland, Frankreich und der Schweiz hat Quanten-Bits, kurz Qubits, in einer neuen Form umgesetzt. Eines Tages könnten diese die Informationseinheiten eines Quantencomputers sein. Bislang hatten die Wissenschaftler Qubits in Form von einzelnen Elektronen realisiert. Das führte jedoch zu Störeffekten und machte die Informationsträger schwer zu programmieren und auszulesen. Dieses Problem beseitigte die Gruppe nun, indem sie Elektronenlöcher statt Elektronen als Qubits nutzte. Das Team berichtet in der Zeitschrift „Nature Materials“.

  • Fundamental properties of spin Seebeck effect unveiled

    Fundamental properties of spin Seebeck effect unveiled | Thermally excited spin waves carry a spin current from the ferromagnet (YIG in this case) into the metal layer. Depending on the YIG thickness and the interface condition the amplitude of the spin current as well as transmission properties change. illustraton: Joel Cramer, JGU

    Direct correlation between temperature dependent generation of spin currents and atomic composition of interfaces found

    Thermoelectric effects are a fundamental building block for the conception and development of new processes for information processing. They enable to re-use waste heat obtained in different processes for the operation of respective devices and thus contribute to the establishment of more energy-efficient, ecofriendly processes. A promising representative of this effect category is the so-called spin Seebeck effect, which became prominent within recent years. This effect allows to convert waste heat into spin currents and thereby to transport energy as well as information in magnetic, electrically insulating materials.

  • Making magnets flip like cats at room temperature

    Making magnets flip like cats at room temperature | Flipping NiMnSb magnet Illustration: Inspire Group, JGU

    Heusler alloy NiMnSb could prove valuable as a new material for digital information processing and storage. The direction of its magnetic field can be switched by changing the direction of an electric current running through it.

  • Making spintronic neurons sing in unison

    Johan Åkerman. Photo: Johan Wingborg

    What do fire flies, Huygens’s wall clocks, and even the heart of choir singers, have in common? They can all synchronize their respective individual signals into one single unison tone or rhythm. Now researchers at University of Gothenburg have taught two different emerging classes of nano-scopic microwave signal oscillators, which can be used as future spintronic neurons, to sing in unison with their neighbours. Earlier this year, they announced the first successful synchronization of five so-called nano-contact spin torque oscillators. In that system, one of the nano-contacts played the role of the conductor, deciding which note to sing, and the other nano-contacts happily followed her lead.

  • Manipulating Electron Spins Without Loss of Information

    Electrons rotate on their way through the chip in a spiral pattern. Adjustments in the voltage lead to changes in this pattern and thus the orientation of the spin can be controlled. University of Basel, Department of Physics

    Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

  • Physicists Couple Distant Nuclear Spins Using a Single Electron

    For the first time, researchers at the University of Basel have coupled the nuclear spins of distant atoms using just a single electron. Three research groups from the Department of Physics took part in this complex experiment, the results of which have recently been published in the journal Nature Nanotechnology.

  • Physiker weisen für Magnonen Supraströme bei Raumtemperatur nach

    Physiker weisen für Magnonen Supraströme bei Raumtemperatur nach | Professor Dr. Burkhard Hillebrands, TU Kaiserslautern Koziel/ TU Kaiserslautern

    Supraleiter zeigen faszinierende Quantenphänomene. Allerdings treten diese in der Regel nur bei Temperaturen weit unter dem Gefrierpunkt auf. Für bestimmte Quantenteilchen, die Magnonen, haben Physiker um Professor Dr. Burkard Hillebrands von der TU Kaiserslautern einen neuartigen Strom von Magnonen, einen Suprastrom, nun erstmals bei Raumtemperatur nachgewiesen. An der Arbeit waren auch theoretische Physiker aus Israel und der Ukraine beteiligt. Die Erkenntnisse könnten helfen, etwa die Datenverarbeitung wesentlich leistungsfähiger machen. Die Studie wurde in der renommierten Fachzeitschrift „Nature Physics“ veröffentlicht.

  • Shielded Quantum Bits

    Schematic representation of the new spin qubit consisting of four electrons (red) with their spins (blue) in their semiconductor environment (grey). Copyright: Maximilian Russ/Guido Burkard

    A theoretical concept to realize quantum information processing has been developed by Professor Guido Burkard and his team of physicists at the University of Konstanz. The researchers have found ways to shield electric and magnetic noise for a short time. This will make it possible to use spins as memory for quantum computers, as the coherence time is extended and many thousand computer operations can be performed during this interval. The study was published in the current issue of the journal “Physical Review Letters”.

  • Spintronik: Effizientes Materialsystem für die wärmeunterstützte Datenspeicherung

    Die Membran besitzt Poren im Abstand von 105 Nanometern, die als Haftstellen für die magnetischen Domänenwände wirken. Bild: HZB

    Ein HZB-Team hat Dünnschichten aus Dysprosium-Kobalt über einer nanostrukturierten Membran an BESSY II untersucht. Sie zeigten, dass eine Erwärmung auf nur 80 Grad Celsius ausreicht, um die Magnetisierung von winzigen Nano-Regionen neu auszurichten. Dies ist weit weniger als bislang für die wärmeunterstützte magnetische Datenspeicherung (Heat Assisted Magnetic Recording) nötig war.