Spectroscopic fingerprints of the frustrated magnetic order in Li2VOSiO4Li2VOSiO4: A t–Jt–J model study

We have analyzed theoretically the photoemission spectra of the insulating compound Li2VOSiO4Li2VOSiO4. Recently, this compound has been proposed as the first experimental realization of the frustrated J1–J2J1–J2 Heisenberg model. Although it is well known that Li2VOSiO4Li2VOSiO4 is magnetically ordered in a collinear arrangement below TN=2.8K, there is some controversy about the coexistence of two collinear phases above TNTN. Using a generalized t–Jt–J model we have obtained a complex spectral structure that can be traced back to the underlying collinear magnetic structures. We discuss the possibility to use ARPES experiments as a way to discern among the different scenarios proposed in the literature.