Realization of tilted Dirac-like microwave cone in superconducting circuit lattices

  1. Amir Youssefi,
  2. Ahmad Motavassal,
  3. Shingo Kono,
  4. Seyed Akbar Jafari,
  5. and Tobias J. Kippenberg
Dirac-like band crossings are paradigms in condensed matter systems to emulate high-energy physics phenomena. They are associated with two aspects: gap and tilting. The ability to design
sign-changing gap gives rise to band topology, whereas the tilting of band crossings which is a gateway for large gravity-like effects remains uncharted. In this work, we introduce an experimental platform to realize tilted Dirac-like microwave cone in large-scale superconducting circuit lattices. The direction and magnitude of the tilt can be controlled by engineering the axially preferred second neighbor coupling. We demonstrate three lattices with 731-site LC resonator featuring tilt values of up to 59% of relative difference in the opposite-direction group velocities. This is obtained by reconstructing the density of states (DOS) of measured microwave resonance frequencies. Harnessing the tilt of Dirac-like band crossings lays the foundation for weaving the fabric of an emergent solid-state spacetime.