collaborators
Showing math.SPShow all

5 papers · 1 filter

math.SP2025

Absence of flat bands for discrete periodic graph operators with generic potentials

Matthew Faust, Ilya Kachkovskiy

We show that Schrödinger-type operators on discrete connected periodic graphs do not have flat bands for generic potentials.

math.SP2025

Perturbative diagonalization and spectral gaps of quasiperiodic operators on with monotone potentials

Ilya Kachkovskiy, Leonid Parnovski, Roman Shterenberg

We obtain a perturbative proof of localization for quasiperiodic operators on with one-dimensional phase space and monotone sampling functions, in the regime of smal…

math.SP2025

On gaps in the spectra of quasiperiodic Schrödinger operators with discontinuous monotone potentials

Ilya Kachkovskiy, Leonid Parnovski, Roman Shterenberg

We show that, for one-dimensional discrete Schrödinger operators, stability of Anderson localization under a class of rank one perturbations implies absence of intervals in spectr…

math.SP2024

Sharp arithmetic delocalization for quasiperiodic operators with potentials of semi-bounded variation

Svetlana Jitomirskaya, Ilya Kachkovskiy

We obtain the sharp arithmetic Gordon's theorem: that is, absence of eigenvalues on the set of energies with Lyapunov exponent bounded by the exponential rate of approximation of f…

math.SP2024

Sharp arithmetic localization for quasiperiodic operators with monotone potentials

Svetlana Jitomirskaya, Ilya Kachkovskiy

We prove the universality of sharp arithmetic localization for all one-dimensional quasiperiodic Schrödinger operators with anti-Lipschitz monotone potentials.