Monolayer graphene at charge neutrality in a quantizing magnetic field is quantum Hall ferromagnet. Due to the spin and valley (near) degeneracies, there plethora of possible ground states. Previous theoretical work, based on stringent ultra short-range assumption symmetry-allowed interactions, predicts phase diagram with distinct regions spin-polarized, canted antiferromagnetic, inter-valley coherent, density wave order. While early experiments suggested that system was antiferromagnetic...

The magnetic flux periodicity of $\frac{hc}{2e}$ is a well-known manifestation Cooper pairing in typical $s$-wave superconductors. In this paper we theoretically show that the two-dimensional second order topological superconductor, which features zero-energy Majorana modes localized at corners sample, $\frac{hc}{e}$ instead. We further changes back to transition topologically trivial where hybridize with bulk states, demonstrating doubling nontrivial topology state.

We study magnon transmission across gate-controlled junctions in the $n=0$ manifold of Landau levels monolayer graphene presence both spin and valley Zeeman fields. Specifically, we consider $1|\ensuremath{-}1|1$ sandwich geometry. The nature interfaces between regions different filling turns out to be crucial for transmission. Using Hartree-Fock approximation, find that either or degrees freedom occupied one-body states rotate interfaces. If exhibit rotation, then is suppressed at high...

We investigate the effects of introducing a boost (a Zeeman field parallel to spin quantization axis) at proximitized helical edge two-dimensional (2D) quantum Hall insulator. Our self-consistent analysis finds that Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting phase may emerge when is larger than critical value tied induced pairing gap. A nontrivial consequence retaining 2D bulk in model this boundary FFLO state supports finite magnetization as well current (flowing along edge)....

We study the ground state of a system with an interface between $\ensuremath{\nu}=4$ and $\ensuremath{\nu}=3$ in quantum Hall regime. Far from interface, for range interaction strengths, region is fully polarized but unpolarized. Upon varying strength interactions width chooses one two distinct edge/interface phases. In phase $A$, stabilized wide interfaces, spin good number, there are no gapless long-wavelength fluctuations. $B$, narrow symmetry spontaneously broken at Hartree-Fock level....

A hybrid setup consisting of a superconductivity-proximitized quantum spin Hall insulator and anomalous (QAH) is proposed for chiral injection electrons into the Majorana bound state (MBS). An unexplored region phase space involving Zeeman-field-induced boost helical edge then detection MBS. Two-dimensional transport simulations our are compared with corresponding in absence QAH region, when moderate potential magnetic disorder included. The remarkable contrast between two results...

We study magnon transmission across gate-controlled junctions in the $n=0$ manifold of Landau levels monolayer graphene, presence both spin and valley Zeeman fields. Specifically, we consider $1|-1|1$ sandwich geometry. The nature interfaces between regions different filling turns out to be crucial for transmission. Using Hartree-Fock approximation, find that either or degrees freedom occupied one-body states rotate interfaces. If exhibit rotation, is suppressed at high energies, while if...

Nanoscale defects such as Nitrogen Vacancy (NV) centers can serve sensitive and non-invasive probes of electromagnetic fields fluctuations from materials, which in turn be used to characterize these systems. Here we specifically discuss how NV directly probe time-reversal symmetry breaking (TRSB) phenomena low-dimensional conductors magnetic insulators. We argue that the relaxation rate vary dramatically depending on whether its dipole points towards or away TRSB material. This effect arises...

We investigate the effects of introducing a boost (a Zeeman field parallel to spin quantization axis) at proximitized helical edge two-dimensional (2D) quantum Hall insulator. Our self-consistent analysis finds that Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) superconducting phase may emerge when is larger than critical value tied induced pairing gap. A non-trivial consequence retaining 2D bulk in model this boundary FFLO state supports finite magnetization as well current (flowing along edge)....

Monolayer graphene at charge neutrality in a quantizing magnetic field is quantum Hall ferromagnet. Due to the spin and valley (near) degeneracies, there plethora of possible ground states. Previous theoretical work, based on stringent ultra short-range assumption symmetry-allowed interactions, predicts phase diagram with distinct regions spin-polarized, canted antiferromagnetic, inter-valley coherent, density wave order. While early experiments suggested that system was antiferromagnetic...