Manipulating ultracold polar molecules with microwave radiation: the influence of hyperfine structure

TL;DR

This paper calculates microwave spectra of ultracold KRb molecules considering hyperfine interactions, revealing how microwave transitions can manipulate hyperfine states and how external fields influence spectral complexity, with implications for quantum computing.

Contribution

It provides detailed calculations of hyperfine-influenced microwave spectra of ultracold KRb molecules, highlighting control methods using electric and magnetic fields.

Findings

Microwave transitions can transfer molecules between hyperfine states due to nuclear quadrupole interactions.

Hyperfine splittings can complicate quantum computing applications with ultracold molecules.

Applying magnetic fields simplifies spectra of molecules oriented in electric fields.

Abstract

We calculate the microwave spectra of ultracold KRb alkali metal dimers, including hyperfine interactions and in the presence of electric and magnetic fields. We show that microwave transitions may be used to transfer molecules between different hyperfine states, but only because of the presence of nuclear quadrupole interactions. Hyperfine splittings may also complicate the use of ultracold molecules for quantum computing. The spectrum of molecules oriented in electric fields may be simplified dramatically by applying a simultaneous magnetic field.