Data for: Many-body thermodynamics on quantum computers via partition function zeros

Partition functions are ubiquitous in physics: they are important in
determining the thermodynamic properties of many-body systems, and in
understanding their phase transitions. As shown by Lee and Yang,
analytically continuing the partition function to the complex plane allows
us to obtain its zeros and thus the entire function. Moreover, the scaling
and nature of these zeros can elucidate phase transitions. Here we show
how to find partition function zeros on noisy intermediate-scale trapped
ion quantum computers in a scalable manner, using the XXZ spin chain model
as a prototype, and observe their transition from XY-like behavior to
Ising-like behavior as a function of the anisotropy. While quantum
computers cannot yet scale to the thermodynamic limit, our work provides a
pathway to do so as hardware improves, allowing the future calculation of
critical phenomena for systems beyond classical computing limits.