title: Nonclassical correlations between terahertz-bandwidth photons mediated by rotational quanta in hydrogen molecules.
abstract: Quantum photonics offers much promise for the development of new technologies. The ability to control the interaction of light and matter at the level of single quantum excitations is a prerequisite for the construction of potentially powerful devices. Here we use the rotational levels of a room temperature ensemble of hydrogen molecules to couple two distinct optical modes at the single photon level using femtosecond pulses with 2 THz bandwidth. We observe photon correlations that violate a Cauchy-Schwarz inequality, thereby verifying the creation of a nonclassical state. This work demonstrates the rich potential of molecules for use in ultrafast quantum photonic devices.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Bustard
authors.forename: Jennifer
authors.initials: J
authors.lastname: Erskine
authors.forename: Duncan G
authors.initials: DG
authors.lastname: England
authors.forename: Josh
authors.initials: J
authors.lastname: Nunn
authors.forename: Paul
authors.initials: P
authors.lastname: Hockett
authors.forename: Rune
authors.initials: R
authors.lastname: Lausten
authors.forename: Michael
authors.initials: M
authors.lastname: Spanner
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Sussman