Efficient Spin-1 Ground States Preparation with Qutrit-based Quantum Hardware*

Recent developments in Noisy Intermediate Scale Quantum (NISQ) devices have gained traction due to their capability to simulate many-body systems. Simulating higher spin systems with such devices, unlike spin ½ systems, requires multiple qubits to encode each spin site. This introduces an additional level of complexity when simulating higher spin systems in order to characterize their eigenstates and dynamics. In this work, we extend the existing qubit gate set to include single qutrit gates obtained by accessing the second excited state of IBM Quantum's hardware. We achieve this by running calibration experiments to construct the appropriate microwave pulse sequences which produce a set of single qutrit gates. To then demonstrate the efficacy of these gates, we simulate one-dimensional spin-1 systems and their ground states by mapping the states of each site to those of a 3-level transmon for varying chain lengths. The efficiency of qutrit encoding to prepare ground states demonstrated here suggests that qutrits could be used to study interesting physics of spin-1 systems more elegantly than the conventional qubit-based simulation.