Monotonically convergent optimal control theory of quantum systems with spectral constraints on the control field

TL;DR

This paper introduces a new algorithm for quantum control that enforces spectral constraints on control fields, improving molecular alignment efficiency while respecting experimental limitations.

Contribution

A novel monotonically convergent algorithm that incorporates spectral constraints into quantum control optimization, extendable to arbitrary filters.

Findings

Effective control of molecular alignment using spectral constraints

Ability to select specific rotational transitions for high efficiency

Potential for experimental implementation with pulse shaping techniques

Abstract

We propose a new monotonically convergent algorithm which can enforce spectral constraints on the control field (and extends to arbitrary filters). The procedure differs from standard algorithms in that at each iteration the control field is taken as a linear combination of the control field (computed by the standard algorithm) and the filtered field. The parameter of the linear combination is chosen to respect the monotonic behavior of the algorithm and to be as close to the filtered field as possible. We test the efficiency of this method on molecular alignment. Using band-pass filters, we show how to select particular rotational transitions to reach high alignment efficiency. We also consider spectral constraints corresponding to experimental conditions using pulse shaping techniques. We determine an optimal solution that could be implemented experimentally with this technique.