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Updated: Jul 10, 2026

Magnetically Induced Rotating Rayleigh-Taylor Instability

Magnetically Induced Rotating Rayleigh-Taylor Instability

Published on: March 3, 2017

Generalized rotating-wave approximation for arbitrarily large coupling.

¹School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, United Kingdom. e.irish@qub.ac.uk

Physical Review Letters

|November 13, 2007

Summary

A new generalized rotating-wave approximation improves energy level accuracy for spin-boson Hamiltonians. This enhanced method is accurate across various coupling strengths and detunings, benefiting solid-state experiments.

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Area of Science:

Quantum mechanics
Condensed matter physics

Background:

The spin-boson Hamiltonian is a fundamental model in quantum mechanics describing the interaction between a two-level system and a bosonic bath.
The rotating-wave approximation (RWA) is a common technique used to simplify calculations involving such systems, but it has limitations.

Purpose of the Study:

To present a generalized version of the rotating-wave approximation for the single-mode spin-boson Hamiltonian.
To demonstrate that this generalized approximation yields more accurate energy level expressions compared to standard methods.

Main Methods:

A generalized rotating-wave approximation was developed.
A specific change of basis was performed before eliminating off-resonant terms in the Hamiltonian.

Main Results:

The generalized approximation provides a significantly more accurate expression for the system's energy levels.
The method's accuracy is maintained for all coupling strengths.
It is also effective for a wide range of detuning values.

Conclusions:

The generalized rotating-wave approximation offers improved accuracy for the spin-boson model.
This method is applicable across diverse parameter regimes.
Potential applications exist in experimental solid-state physics.