Seminar: Superconductivity in altermagnets

Recently, a new form of magnetism, called altermagnetism, has been discovered, beyond the previously well-established ferro- and antiferromagnetism possibilities. Altermagnets break spin-degeneracy, as in a ferromagnet, but with a momentum dependent spin splitting resulting in zero net magnetization, as in antiferromagnets. Due to their unique magnetization, altermagnets also produce intriguing possibilities for other ordered phases of matter. Magnetism and superconductivity are two of the most celebrated quantum phases of matter and usually have a ‘friend-foe’ dichotomous relation, but combining superconductivity with altermagnetism turns out to open for new exceptional possibilities. In this talk I will show several novel effects occurring when superconductivity appears in an altermagnet, including finite momentum pairing, field-induced superconductivity, and a perfect superconducting diode effect, as well as demonstrate constraints on the possible superconducting pairing.