Quantum Brain
← Back to papers

A pedagogical derivation of the first-order effective Hamiltonian for the two-mode Jaynes-Cummings model

Alejandro R. Urzúa·January 23, 2026
Quantum Physicsphysics.ed-ph

AI Breakdown

Get a structured breakdown of this paper — what it's about, the core idea, and key takeaways for the field.

Abstract

This work presents a pedagogical and self-contained derivation of the first-order effective Hamiltonian for the two-mode Jaynes-Cummings model in the dispersive regime. A perturbative unitary transformation removes nonresonant atom-field terms, revealing dispersive frequency shifts leading to an atom-induced effective beam-splitter interaction between the field modes. The resulting Hamiltonian is diagonalized through a simple geometric rotation in the two-mode bosonic space, providing a transparent interpretation of the underlying dynamics. The exposition emphasized clarity and physical insight, making effective Hamiltonian methods accessible for teaching and learning in multimode light-matter interactions.

Related Research

Quantum Intelligence

Ask about quantum research, companies, or market developments.