The strength of weak coupling

Research output: Working paperPreprint

Abstract

A paradoxical idea in quantum transport is that attaching weakly-coupled edges to a large base graph creates high-fidelity quantum state transfer. We provide a mathematical treatment that rigorously prove this folklore idea. Our proofs are elementary and build upon the Feshbach-Schur method from perturbation theory. We also show the idea is effective in circumventing Anderson localization in spin chains and finding speedups in hitting times useful for quantum search.
Original languageEnglish
Publication statusUnpublished - 9 Dec 2025

Keywords

  • quant-ph
  • math.CO

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