Zobrazeno 1 - 10
of 77
pro vyhledávání: '"Akhmerov, Anton R."'
A common technique in the study of complex quantum-mechanical systems is to reduce the number of degrees of freedom in the Hamiltonian by using quasi-degenerate perturbation theory. While the Schrieffer--Wolff transformation achieves this and constru
Externí odkaz:
http://arxiv.org/abs/2404.03728
Axial vectors, such as current or magnetization, are commonly used order parameters in time-reversal symmetry breaking systems. These vectors also break isotropy in three dimensional systems, lowering the spatial symmetry. We demonstrate that it is p
Externí odkaz:
http://arxiv.org/abs/2310.18400
The non-Hermitian skin effect is a phenomenon in which an extensive number of states accumulates at the boundaries of a system. It has been associated to nontrivial topology, with nonzero bulk invariants predicting its appearance and its position in
Externí odkaz:
http://arxiv.org/abs/2308.00776
We present a systematic method to design arbitrary energy-phase relations using parallel arms of two series Josephson tunnel junctions each. Our approach employs Fourier engineering in the energy-phase relation of each arm and the position of the arm
Externí odkaz:
http://arxiv.org/abs/2307.04830
Publikováno v:
SciPost Phys. 16, 044 (2024)
Braiding of Majorana states demonstrates their non-Abelian exchange statistics. One implementation of braiding requires control of the pairwise couplings between all Majorana states in a trijunction device. To have adiabaticity, a trijunction device
Externí odkaz:
http://arxiv.org/abs/2307.03299
Publikováno v:
SciPost Phys. 16, 120 (2024)
Disorder can localize the eigenstates of one-dimensional non-Hermitian systems, leading to an Anderson transition with a critical exponent of 1. We show that, due to the lack of energy conservation, the dynamics of individual, real-space wave packets
Externí odkaz:
http://arxiv.org/abs/2301.07370
Publikováno v:
SciPost Phys. 15, 114 (2023)
We derive a $\mathbb{Z}_4$ topological invariant that extends beyond symmetry eigenvalues and Wilson loops and classifies two-dimensional insulators with a $C_4 \mathcal{T}$ symmetry. To formulate this invariant, we consider an irreducible Brillouin
Externí odkaz:
http://arxiv.org/abs/2209.00029
Publikováno v:
SciPost Phys. 14, 047 (2023)
Josephson junctions in a two-dimensional electron gas with spin-orbit coupling are a promising candidate to realize topological superconductivity. While it is known that the geometry of the junction strongly influences the size of the topological gap
Externí odkaz:
http://arxiv.org/abs/2205.05689
Publikováno v:
SciPost Phys. Core 5, 053 (2022)
We show that topological defects in quadrupole insulators do not host quantized fractional charges, contrary to what their Wannier representation indicates. In particular, we test the charge quantization hypothesis based on the Wannier representation
Externí odkaz:
http://arxiv.org/abs/2202.07675
Publikováno v:
SciPost Phys. 12, 017 (2022)
The multi-terminal Josephson effect allows DC supercurrent to flow at finite commensurate voltages. Existing proposals to realize this effect rely on nonlocal Andreev processes in superconductor-normal-superconductor junctions. However, this approach
Externí odkaz:
http://arxiv.org/abs/2104.11239