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Topology in quantum mechanics is applied to determine if a system is trivial or topological. A condensed matter system has a topological nature if the general wave function describing it is adiabatically distinct from the atomic limit. Although nontrivial topology has been known to exist in quantum Hall systems for nearly four decades, recent years have seen a massive resurgence in the interest of topological matter stemming from a series of ground-breaking discoveries. In many cases, topological quantum mechanics is achieved in systems involving superconductors with highlights including: Majorana Fermions in nanowire devices; unconventional electron pairing in layered oxides and the decoding high temperature superconductivity; superconducting thin films of strontium ruthenate; topological superconductivity in UTe2; coupling superconductivity into chiral (topological) molecules; and topological superconductivity and magnetism in twisted bilayer graphene.

The incredible progress made in materials research over the past decade and half has been central to the rapid development of unconventional superconductivity in topological quantum materials. These include the development of atomically-controlled crystals, thin films and interfaces, and the manipulation of pristine two-dimensional materials and superlattices. The widespread interest and progress in unconventional superconductivity and topology in such advanced materials continues to accelerate; however, a targeted, interdisciplinary, approach is required in order to achieve full understanding and the discovery of new science. This workshop brings together world-leading scientists from a broad range of disciplines working on overlapping themes involving correlated electrons and superconductivity in topological systems. These communities had an opportunity to appreciate how these areas are interlinked thereby stimulating further understanding and new collaborations.

For videos of the talks and further information, please visit the workshop home page.

The first Online SPICE-Workshop on 2D van der Waals Spin Systems has been successfully completed. Scientists from all over the world have attended our workshop from 4th to 7th August, 2020. Thank you for your active participation!

We are delighted to see the enormous interest in the new Online SPICE-SPIN+X Seminars. We had 500 participants in Zoom (to capacity) and over 300 watching life on YouTube. Tomas Jungwirth gave the inaugural seminar on Antiferromagnetic spintronics: from memories to ultra-fast optics and topological transport. His talk is available on the SPICE YouTube Channel and can also be reached to the direct link here.

 

To receive by e-mail the Zoom Meeting log-in information and the announcements, please sign up to the seminars e-mail list (no further announcements on the on-line seminars will be sent by the news-from-spice mailing list). You can click here for the e-mail list sign-up form or find it directly at the SPICE-SPIN+X Seminars website.

In the time of physical distancing, it is more important than ever to remain close socially and scientifically. The Spin Phenomena Interdisciplinary Center SPICE and the Collaborative Research Center SPIN+X have joined forces to start a weekly condensed matter seminar series with an emphasis on spin and topological physics.

The talks will be given via Zoom and live streamed on the SPICE YouTube Channel, with most of them also available afterwards on the channel.

To receive by e-mail the Zoom Meeting log-in information and the announcements, please sign up to the seminars e-mail list (no further announcements on the on-line seminars will be sent by the news-from-spice mailing list). You can click here for the e-mail list sign-up form or find it directly at the SPICE-SPIN+X Seminars website. To listen to the talk through the livestreaming, simply go to the SPICE YouTube Channel at the time of the seminar. Attendance is of course free.

Elastic Tuning and Response of Electronic Order

New physical phenomena have emerged from a particularly strong coupling between a materials’ elasticity and its symmetry-broken electronic quantum phases. Examples are reversible superelasticity with large recoverable strain in iron-based materials, strong nonlinear elastic response with violation of Hooke’s law and critical elasticity in pressurized organic charge-transfer salts, a doubling of the superconducting transition temperature in strained strontium ruthenate, strain-induced charge order in cuprate superconductors, as well as nematicity in iron-based superconductors. Static and dynamic strain manipulation has emerged as a new knob to tune and shape a material’s electronic properties.

For videos of the talks and further information, please visit the workshop home page.

Novel Electronic and Magnetic Phases in Correlated Spin-Orbit Coupled Oxides

The interplay between spin, orbit and electron correlation has emerged as a new paradigm in contemporary condensed matter physics and represents a rich playground for the realization of novel quantum state of matters with exotic electronic and magnetic properties including Dirac-Mott insulators, Lifshitz/Slater phases, Multipolar and Kitaev model magnetism, unconventional superconductivity and topological physics.

For videos of the talks and further information, please visit the workshop home page.

Molecular Electro-Opto-Spintronics

Molecular electronics originally promised miniaturization of molecular devices using Nature’s smallest building blocks to allow for novel electronic function by simply altering the chemical structure of the molecular component. Molecular electronics has evolved towards a complementary technology to silicon-based electronics, providing functionalities not possible with classical electronic devices. After more than 40 years of experiments, it remains a challenge to rationally design molecule-electrode junctions due the complex interplay between electronic structure and the chemical/supramolecular arrangement of the interfaces. Unlike traditional CMOS electronics, comprehensive design rules for molecular junctions are not available yet. Only bits and pieces have been published scattered across disciplines, including interface engineering, supramolecular chemistry, surface science, computational science, physics, chemistry, optics, biology and micro/nanofabrication.

Antiferromagnetic Spintronics: from topology to neuromorphic computing

The new field of antiferromagnetic spintronics focuses on making antiferromagnets active elements of spintronic devices. The higher complexity of the ordered phase and parameter space in antiferromagnets have given rise to new avenues of basic research that range from topological quasiparticle dynamic manipulation, multipole order effects, ultra-fast dynamics, and even applications towards neuromorphic computing and IoT.

The new field is of interest to the strongly correlated effects community and the community focused on topological matter. It has connected to the current ferromagnetic spintronics research by creating entirely new ways of rethinking spin phenomena in antiferromagnets, while benefiting from the pioneering works in antiferromagnetic materials.

For videos of the talks and further information, please visit the workshop home page.

YRLGW: Topomagnetism Is Coming: Relativity and Correlations in Topological Magnets

Remarkable advances in strongly correlated and relativistic condensed matter physics have been made over the past decade by these largely non-interacting communities. Interestingly, their attention recently focused on the same grand challenges such as room-temperature quantum chiral edge modes, topological superconductivity, or topological computation.

The research of nonmagnetic materials culminated in predicting that approximately one third of them exhibit topological electronic structure. In contrast, the investigation of topological magnets is progressing at much slower pace albeit time-reversal symmetry broken topological phases demand magnetic order. For a long time, low-dimensional topological systems were anticipated to be naturally incompatible with robust magnetism. However, recent theoretical and experimental efforts have revealed low-dimensional as well as 3D topological insulators and Weyl semimetal magnets. The relativistic phenomena, e.g. the spin Hall, quantum spin Hall, or magnetic spin-Hall effect, were originally predicted within the single-particle picture. However, realistic predictions of magnetic materials, requires inclusion of the electronic correlations. Conversely, the correct description of strongly correlated magnets with high atomic numbers needs to include spin-orbit coupling phenomena.

Skyrmionics Workshop for Young Researcher

The recent interest skyrmionic materials have provided a new playground for the study of topological solitons. The topologically non-trivial magnetic spin textures can facilitate fast current-induced magnetization manipulation, which makes these exotic textures widely advantageous for many areas of technology, from spintronics to neuromorphic computing.

The current research effort is to detect, visualize, and manipulate the magnetic states: by momentum space mapping such as small angle neutron scattering, by real space detection such as Lorentz transmissions electron microscopy, by transport such as the topological Hall effect, and manipulation by external fields resulting in the skyrmion Hall effect. The extensive study of their transport properties and the ability to create a controlled environment for the creation and annihilation of magnetic skyrmions are essential steps towards the realization of skyrmion-based devices. Skyrmions can exist in a multitude of systems, bulk, multilayer heterostructures, and films with a variety of shapes due to the internal symmetry and the competition of exchange interactions. The increasing number of skyrmion hosting materials combined with the rapid growth of the research field provides a promising prospect to overcome the challenges for next-generation devices.

For videos of the talks and further information, please visit the workshop home page.