We simulate a zero-temperature pure Z3 Lattice Gauge Theory in 2+1 dimensions by using an iPEPS (Infinite Projected Entangled-Pair State) ansatz for the ground state. Our results are therefore directly valid in the thermodynamic limit. They clearly show two distinct phases separated by a phase transition. We introduce an update strategy that enables plaquette terms and Gauss-law constraints to be applied as sequences of two-body operators. This allows the use of the most up-to-date iPEPS algorithms. From the calculation of spatial Wilson loops we are able to prove the existence of a confined phase. We show that with relatively low computational cost it is possible to reproduce crucial features of gauge theories. We expect that the strategy allows the extension of iPEPS studies to more general LGTs.
On 19 September, Ignacio Cirac, Director of the Theory Department at the Max Planck Institute of Quantum Optics, received the first La Vanguardia Prize in the category "Innovation", which the Spanish daily by the same name awarded for the first time on the occasion of its 142nd anniversary in 2023. The prize was ceremoniously presented to him by Spain's King Felipe VI, who graced the event together with his wife, Queen Letizia.
Focusing on so-called symmetry-protected topological (SPT) phases, the theorist uncovered some essential but previously unknown properties. Her findings further our understanding of STP phases in open systems.
The simulation of quantum chemical processes promises a lot of progress, such as the discovery of new chains of reactions, new synthetic materials or pharmaceuticals. But it is an enormous task, which known methods have failed to date. For classical supercomputers, the molecules are too complex, and for quantum simulations with cold atoms, the technological hurdles are still too high. In a new paper, theorists have now developed...
In his thesis, he studied and applied methods from quantum information to, among other things, find the ground state in complex quantum systems. As a next career step, he will start working as a Quantum Application Engineer at a Munich start-up company.
NISQ computers need quantum entanglement as a key resource to perform computations. But the presence of entanglement can also in some cases be a threat to their accuracy, like a recently published paper shows.
