Observation of parity-time symmetry breaking transitions in a dissipative Floquet system of ultracold atoms

Abstract Open physical systems with balanced loss and gain, described by non-Hermitian parity-time $$\left( {{\cal P}{\cal T}} \right)$$ P T reflection symmetric Hamiltonians, exhibit a transition which could engender modes that exponentially decay or grow with time, and thus spontaneously breaks the $${\cal P}{\cal T}$$ P T -symmetry. Such $${\cal P}{\cal T}$$ P T -symmetry-breaking transitions have attracted many interests because of their extraordinary behaviors and functionalities absent in closed systems. Here we report on the observation of $${\cal P}{\cal T}$$ P T -symmetry-breaking transitions by engineering time-periodic dissipation and coupling, which are realized through state-dependent…

• NS
  National Science Foundation
• NN
  National Natural Science Foundation of China

  Awards: 11804406, 11774436
• SY
  Sun Yat-sen University
• DO
  Division of Materials Research