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Updated: Jul 1, 2025

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Quantum criticality in chains of planar rotors with dipolar interactions
Tobias Serwatka1, Pierre-Nicholas Roy1
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Abstract:
In this work, we perform a density matrix renormalization group study of chains of planar rotors interacting via dipolar interactions. By exploring the ground state from weakly to strongly interacting rotors, we find the occurrence of a quantum phase transition between a disordered and a dipole-ordered quantum state. We show that the nature of the ordered state changes from ferroelectric to antiferroelectric when the relative orientation of the rotor planes varies and that this change requires no modification of the overall symmetry. The observed quantum phase transitions are characterized by critical exponents and central charges, which reveal different universality classes ranging from that of the (1 + 1)D Ising model to the 2D classical XY model.
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