Pulse design without rotating wave approximation

TL;DR

This paper develops methods for designing fast, realistic control pulses to invert two-level quantum systems without relying on the rotating-wave approximation, addressing singularities and proposing numerical solutions.

Contribution

It introduces new pulse design techniques that avoid singularities and enable rapid population inversion beyond adiabatic limits without the rotating-wave approximation.

Findings

Successfully designed pulses that invert populations faster than adiabatic methods.

Proposed methods to cancel or avoid singularities in pulse functions.

Demonstrated numerical minimization approach for complex pulse designs.

Abstract

We design realizable time-dependent semiclassical pulses to invert the population of a two-level system faster than adiabatically when the rotating-wave approximation cannot be applied. Different approaches, based on the counterdiabatic method or on invariants, may lead to singularities in the pulse functions. Ways to avoid or cancel the singularities are put forward when the pulse spans few oscillations. For many oscillations an alternative numerical minimization method is proposed and demonstrated.