Physics

Electron

Bloch oscillations

Quantization (signal processing)

Magnetic field

Quantum Hall effect

Condensed matter physics

Graphene

Computer science

Quantum mechanics

Computer vision

Landau quantization

Quantum oscillations

Fermi gas

Nature Physics

Many intriguing phenomena occur for electrons under strong magnetic fields1,2. Recently, it was shown that an appropriate strain texture in graphene could induce a synthetic gauge field3–6, in which electrons behave as they do in a real magnetic field7–11. This enabled the control of quantum transport by mechanical means and allowed the unreached high-field regime to be explored. Such synthetic gauge fields have been achieved in molecular12 and photonic13 lattices. Here we report an experimental realization of a giant uniform pseudomagnetic field in acoustics by introducing a simple uniaxial deformation to the acoustic graphene. The controllability of our macroscopic platform enables us to observe the acoustic Landau levels in frequency-resolved spectroscopy and their spatial localization in pressure-field distributions. We further visualize the quantum-Hall-like edge states (connected to the zeroth Landau level), which have been elusive owing to the difficulty in creating large-area uniform pseudomagnetic fields5,6. These results, consistent with our full-wave simulations, establish a complete framework for artificial structures under constant pseudomagnetic fields. Our findings may also offer opportunities to manipulate sound in conceptually novel ways. A graphene-like two-dimensional sonic crystal, under uniaxial deformation, experiences a giant uniform pseudomagnetic field. This leads to the quantization of the cyclotron orbits—a kind of acoustic Landau level—that is observed here.

Acoustic Landau quantization and quantum-Hall-like edge states