Quantum processors use the native interactions between effective spins to simulate Hamiltonians or execute quantum gates. In most processors, the native interactions are pairwise, limiting the efficiency of controlling entanglement between many qubits. Here we experimentally demonstrate a new class of native interactions between trapped-ion qubits, extending conventional pairwise interactions to higher order. We realize three- and four-body spin interactions as examples, showing that high-order spin polynomials may serve as a new toolbox for quantum information applications.
@article{arxiv.2209.05691,
title = {Demonstration of three- and four-body interactions between trapped-ion spins},
author = {Or Katz and Lei Feng and Andrew Risinger and Christopher Monroe and Marko Cetina},
journal= {arXiv preprint arXiv:2209.05691},
year = {2023}
}