# Manipulation of spin cluster qubits by electric-field induced modulation of exchange coupling, $g$-factor, and axial anisotropy

## TL;DR

This paper explores how electric fields can manipulate spin cluster qubits by modulating exchange coupling, g-factor, and anisotropy, enabling transitions in decoherence-immune subspaces in molecular spin systems.

## Contribution

It demonstrates the feasibility of controlling spin cluster qubits through electric-field-induced modulation of key Hamiltonian parameters, expanding quantum control methods.

## Key findings

- Transitions between specific spin states can be achieved by modulating g-factor, anisotropy, or exchange interaction.
- Decoherence-immune subspaces can be accessed in simple spin systems like dimers.
- Electric-field control offers a pathway for coherent manipulation of spin cluster qubits.

## Abstract

Electric fields are increasingly used for coherently manipulating spin states in semiconductor and molecular systems. Here we discuss the spin manipulation allowed by the modulation of the main parameters entering the Hamiltonians of molecular spin clusters. In particular, we focus on transitions between states that differ in terms of scalar quantities, such as the total- or the partial-spin sums, but have vanishing expectation values of both the total- and the single-spin projections. These conditions supposedly define subspaces that are immune to the main decoherence mechanisms and that cannot be identified in individual spins, where the total- and the partial-spin sums are fixed or cannot be defined. We show that the desired transitions can in principle be realized in systems as simple as a spin dimer, by modulating the g-factor, the axial anisotropy, or, under suitable conditions, the exchange interaction.