Long-lived Floquet phases in interacting three-dimensional topological semimetals via bicircular laser fields

The use of carefully tailored light fields to manipulate quantum states of matter is an important technique in condensed matter physics. By coupling to the electronic degrees of freedom, they can induce electronic phases that were otherwise absent, for example, by selectively breaking a certain symmetry. One important example is the breaking of time-reversal symmetry by circulary polarized light, which can lead to a photo-induced Hall effect or the splitting of a three-dimensional Dirac node into Weyl nodes. Interestingly, it was recently showed that bicircular laser fields can also break spatial symmetries such as inversion or rotation symmetries, thereby inducing a charge (or spin) density wave order. Importantly, the density wave order can persist even after the light field is turned off, leading to a long-lived light-induced phase. This idea was recently explored in graphene, where it was shown to lead to a long-lived Floquet charge-density wave phase due to a dynamic synchronization transition. Here, we report our findings on coupling bicircular laser light to three-dimensional materials in order to induce spin and/or charge density wave phases. We specifically discuss the effects on topological phases of matter in Dirac and Weyl semimetals.