The hetero junction between the different materials often gives the rectification effect; e.g., pn junction is used for diode. On the other hand, the Josephson junction between the two superconductors is assumed to show symmetric response between the two directions of the current, i.e., the voltage drop $V$ is anti-symmetric with respect to the sign change of the current $I$. However, there should be an asymmetry between the states of charge accumulation on right and left sides of the Josephson junction, which can lead to the nonreciprocal responses. Here we demonstrate theoretically that nonreciprocal $I$-$V$ characteristic appears due to this charging energy difference both in the classical and quantum regimes. This result will pave a route to design and develop the Josephson diode.
Nonreciprocal Equilibrium Josephson Effect of Arbitrary Periodicity from Poor Man's Majorana Zero Modes
Beijing Academy of Quantum Information Sciences（北京量子信息科学研究院）；CAS Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences（中国科学院理论物理研究所）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）
In this work, we propose how to load and manipulate chiral states in a Josephson junction ring in the so called transmon regimen. We characterise these states by their symmetry properties under time reversal and parity transformations. We describe an explicit protocol to load and detect the states within a realistic set of circuit parameters and show simulations that reveal the chiral nature. Finally, we explore the utility of these states in quantum technological nonreciprocal devices.
Nonreciprocal devices effectively mimic the breaking of time-reversal symmetry for the subspace of dynamical variables that they couple, and can be used to create chiral information processing networks. We study the systematic inclusion of ideal gyrators and circulators into Lagrangian and Hamiltonian descriptions of lumped-element electrical networks. The proposed theory is of wide applicability in general nonreciprocal networks on the quantum regime. We apply it to pedagogical and pathological examples of circuits containing Josephson junctions and ideal nonreciprocal elements described by a…
It is necessary to break both time-reversal and parity symmetries to realize a Josephson, or superconducting, diode exhibiting nonreciprocal critical direct-currents (DC). In fact, these conditions are still insufficient. The dependencies of the free energy on the phase difference across the junction and the magnetic field are classified, exhibiting the current-reversion (JR), field-reversion, and field-current reversion conditions, respectively. To exhibit the DC Josephson diode effect, all symmetries satisfying the JR condition need to be broken. The relations of critical currents with respe…
Supercurrent Diode Effect in Josephson Interferometers with Multiband Superconductors
CNR-SPIN（意大利国家研究委员会自旋物理学研究所）；Institute for Theoretical Solid State Physics, Leibniz-Institut für Festkörper- und Werkstoffforschung IFW-Dresden（德累斯顿勒布尼兹固体与材料研究所凝聚态物理理论研究所）；Istituto Lombardo “Accademia di Scienze e Lettere”（伦巴第科学院）；NEST Istituto Nanoscienze-CNR and Scuola Normale Superiore（意大利国家研究委员会纳米科学研究所与比萨高等师范学院）；Universitá di Salerno（萨莱诺大学）
Superconducting diode effect in magnetic superconductors realized by nonreciprocal domain-wall dynamics
Korea Advanced Institute of Science and Technology（韩国科学技术院）；University of Seoul（首尔大学）；Korea Institute for Advanced Study（韩国高等研究院）；University of Illinois at Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；Texas A&M University（德克萨斯农工大学）；University of Texas at Austin（德克萨斯大学奥斯汀分校）
Pseudo-superconducting-diode effect in ferroelectric Josephson junctions
Kavli Institute of Nanoscience, Delft University of Technology（代尔夫特理工大学卡弗里纳米科学研究所）；Department of Quantum Nanoscience, Delft University of Technology（代尔夫特理工大学量子纳米科学系）；Department of Quantum Technology, Netherlands Organisation for Applied Scientific Research (TNO)（荷兰应用科学研究组织（TNO）量子技术部）
Current Induced Hidden States in Josephson Junctions
Harvard University（哈佛大学）；Max Planck Institute for Chemical Physics of Solids（马克斯·普朗克固体化学物理研究所）；University of Basel（巴塞尔大学）；Weizmann Institute of Science（魏茨曼科学研究所）
Molecule-intercalated van der Waals Josephson junctions uncover complex multiband superconductivity
CIC nanoGUNE（CIC纳米技术研究中心）；Centro de Física de Materiales – Materials Physics Center (CFM-MPC) CSIC-EHU（材料物理中心（CFM-MPC）西班牙国家研究委员会-巴斯克大学）；Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Químicas (EHU)（巴斯克大学化学学院先进聚合物与材料系：物理、化学与技术）；Instituto de Nanociencia y Materiales de Aragón (INMA) CSIC-Universidad de Zaragoza（阿拉贡纳米科学与材料研究所（INMA）西班牙国家研究委员会-萨拉戈萨大学）；Laboratorio de Microscopías Avanzadas (LMA), Universidad de Zaragoza（萨拉戈萨大学高级显微镜实验室）；Ikerbasque, Basque Foundation for Science（伊克尔巴斯科科学基金会）
International Center for Quantum Design of Functional Materials (ICQD), University of Science and Technology of China（中国科学技术大学量子功能材料国际设计中心）；Hefei National Laboratory（合肥国家实验室）
Gate-tunable Josephson diodes in magic-angle twisted bilayer graphene
RWTH Aachen University（亚琛工业大学）；Forschungszentrum Jülich（于利希研究中心）；University of Hamburg（汉堡大学）；University of Würzburg（维尔茨堡大学）；National Institute for Materials Science（国立材料研究所）；University of Vienna（维也纳大学）
Nonreciprocal responses of noncentrosymmetric quantum materials attract recent intensive interests, which is essential for the rectification function in diodes. A recent breakthrough is the discovery of superconducting diode effect. The principle to enlarge rectification effect is highly desired to guide the design of superconducting diode. Here, we study theoretically the Josephson junction S/FI/S (S: $d$-wave superconductor, FI: ferromagnetic insulator) on the surface of a topological insulator (TI). The simultaneous existence of $\sinφ$, $\cosφ$ and $\sin 2φ$ terms with almost the same orde…
The asymmetric responses of the system between the external force of right and left directions are called "nonreciprocal". There are many examples of nonreciprocal responses such as the rectification by p-n junction. However, the quantum mechanical wave does not distinguish between the right and left directions as long as the time-reversal symmetry is intact, and it is a highly nontrivial issue how the nonreciprocal nature originates in quantum systems. Here we demonstrate by the quantum ratchet model, i.e., a quantum particle in an asymmetric periodic potential, that the dissipation character…
We theoretically propose a nonreciprocal spin Seebeck effect, i.e., nonreciprocal spin transport generated by a temperature gradient, in antiferromagnetic insulators with broken inversion symmetry. We find that nonreciprocity in antiferromagnets has rich properties not expected in ferromagnets. In particular, we show that polar antiferromagnets, in which the crystal lacks the spatial inversion symmetry, exhibit perfect nonreciprocity --- one-way spin current flow irrespective of the direction of the temperature gradient. We also show that nonpolar centrosymmetric crystals can exhibit nonrecipr…
Nonreciprocal nonhermitian systems provide an unconventional localization mechanism of topological zero modes via the nonhermitian skin effect. While fundamental theoretical characterizations of this effect involve the biorthogonal system of right and left eigenmodes, the recent demonstration of this effect for a zero mode in a robotic metamaterial (Ghatak et al., arXiv:1907.11619) is based on the direct experimental observation of the conventional right eigenvectors. Here I show that such nonreciprocal mechanical metamaterials reveal their underlying biorthogonality in the directly observable…
Magnetic bimerons are topologically nontrivial spin textures in in-plane easy-axis magnets, which can be used as particle-like information carriers. Here, we report a theoretical study on the nonreciprocal dynamics of asymmetrical ferrimagnetic (FiM) bimerons induced by spin currents. The FiM bimerons have the ability to move at a speed of kilometers per second and do not show the skyrmion Hall effect at the angular momentum compensation point. Our micromagnetic simulations and analytical results demonstrate that spin currents are able to induce the nonreciprocal transport and a drift motion o…
