Evaluation of time-dependent correlators after a local quench in iPEPS: hole motion in the t-J model

Understand

Infinite projected entangled pair states (iPEPS) provide a convenient variational description of infinite, translationally-invariant two-dimensional quantum states.

• However, the simulation of local excitations is not directly possible due to the translationally-invariant ansatz.
• Furthermore, as iPEPS are either identical or orthogonal, expectation values between different states as required during the evaluation of non-equal-time correlators are ill-defined.
• Here, we show that by introducing auxiliary states on each site, it becomes possible to simulate both local excitations and evaluate non-equal-time correlators in an iPEPS setting under real-time evolution.