Jacopo D'Alberto — Università degli Studi di Milano #
Simulating the Dynamics of Open Quantum Systems with Quantum Monte Carlo Methods #
The interest in quantum technologies has grown dramatically in recent years. In particular, the attempt to achieve the supremacy of quantum simulators over the classical counterpart, is one of the most challenging tasks nowadays. In this context, understanding properly the features of open quantum systems could be the key to the development of increasingly large and powerful quantum computers. Several approximate approaches were developed in recent years to simulate the dynamics of open quantum systems [1], however the results obtained so far are generally limited to small size systems. Our novel approach is based on the time-dependent Variational Monte Carlo method, used in [2], but it exploits the so-called unravelling of the master equations to obtain a set of quantum trajectories evolving with Stochastic Schrödinger Equations (SSE). By finding the solution for several independent trajectories, we will then be able to reconstruct time-dependent observables equivalent to those coming from the master equations. The application of this method to dissipative Ising models is then shown, employing various variational ansätze ranging from the basic Jastrow wavefunction to more sophisticated ones, such as the renowned Neural Network Quantum States. [1] H. Weimer, A. Kshetrimayum and R. Orús, Rev. Mod. Phys. 93 (2021) [2] M. J. Hartmann and G. Carleo, Phys. Rev. Lett. 122 (2019)