Peter Littlewood is the Head of the Department of Physics at the University of Cambridge. He previously headed the theoretical condensed matter physics group at the Cavendish Laboratory and before that he was Head of the Theoretical Physics Research department at Bell Laboratories, New Jersey, US. His previous research activities include the dynamics of collective transport (charge-density wave, Wigner crystal, vortex lattice); phenomenology and microscopic theory of high-temperature superconductors, transition-metal oxides, and other correlated electronic systems; and optical properties of highly excited semiconductors. He also has interests in theoretical engineering: holographic storage, optical fibers and devices.
When electronic instabilities give rise to three coexisting density waves, interference between them may lock into a state with helicity.