Departamento de Física

Facultad de Ciencia
Universidad de Santiago de Chile

Seminarios de Física en Línea | Miércoles 17 junio - 10:30 h | Dr. Felipe Herrera

06/17/2020 - 10:30
Con mucho agrado los invitamos a participar del seminario que dictará el Dr. Felipe Herrera, académico del Departamento de Física de la Universidad de Santiago de Chile.
El webinar se realizará este miércoles 17 de junio de 2020 a las 10:30 horas mediante la plataforma Zoom.
Para acceder, deben ingresar el día y hora señalados a sus cuentas Zoom con la siguiente información: 
ID de reunión948 1751 0134   
Titulo: Ultrastrong coupling of vibrational and electromagnetic coherence with molecules in infrared nanoantennas
Expositor: Dr. Felipe Herrera
Afiliación: Universidad de Santiago de Chile 
Vibrational strong coupling has emerged as a promising route for manipulating the reactivity of molecules inside infrared cavities. Growing evidence suggests that conventional theories of light-molecule coupling are unable to describe even the basic spectroscopic properties of these systems. We develop a full-quantum methodology to describe the static properties and the sub-picosecond dynamics of a single anharmonic vibrational mode interacting with a quantized infrared cavity field in the strong and ultrastrong coupling regimes. For the first time, we describe the important role of vibrationally-averaged permanent dipoles in the light-matter system dynamics.

The dynamics of vibrational polaritons depends strongly on the shape of the electric dipole function along the vibrational coordinate. We show that a vibrationless polar molecule with a positive slope of the dipole function at equilibrium, can evolve into a polariton wavepacket with a large number of cavity photons starting from the absolute vacuum, for experimentally relevant interaction strengths. This build up of photon amplitude is accompanied by a spontaneous lengthening of the vibrational mode of nearly 10%, comparable with a laser- induced vibrational excitation in free space. We discuss the implications of this unexpected behaviour in the chemical reactivity of molecules inside the cavity.

We also propose a feasible near-field light-matter state preparation scheme to enable the far-field detection of spontaneously generated IR quantum light in plasmonic nanoantennas, and its potential applications in chip-based photonic quantum technology.