title: Anomalous time delays and quantum weak measurements in optical micro-resonators.
abstract: Quantum weak measurements, wavepacket shifts and optical vortices are universal wave phenomena, which originate from fine interference of multiple plane waves. These effects have attracted considerable attention in both classical and quantum wave systems. Here we report on a phenomenon that brings together all the above topics in a simple one-dimensional scalar wave system. We consider inelastic scattering of Gaussian wave packets with parameters close to a zero of the complex scattering coefficient. We demonstrate that the scattered wave packets experience anomalously large time and frequency shifts in such near-zero scattering. These shifts reveal close analogies with the Goos-Hänchen beam shifts and quantum weak measurements of the momentum in a vortex wavefunction. We verify our general theory by an optical experiment using the near-zero transmission (near-critical coupling) of Gaussian pulses propagating through a nano-fibre with a side-coupled toroidal micro-resonator. Measurements demonstrate the amplification of the time delays from the typical inverse-resonator-linewidth scale to the pulse-duration scale.
authors.affiliation: Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Asano
authors.affiliation: Quantum Condensed Matter Research Group, Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.|Nonlinear Physics Centre, RSPE, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: K Y
authors.initials: KY
authors.lastname: Bliokh
authors.affiliation: Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Y P
authors.initials: YP
authors.lastname: Bliokh
authors.affiliation: Quantum Condensed Matter Research Group, Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.|Department of Chemical Physics, Weizmann Institute of Science, Rehovot 7610001, Israel.
authors.forename: A G
authors.initials: AG
authors.lastname: Kofman
authors.affiliation: Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
authors.forename: R
authors.identifier: 0000-0001-8628-7177
authors.initials: R
authors.lastname: Ikuta
authors.affiliation: Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Nonlinear Physics Centre, RSPE, The Australian National University, Canberra, Australian Capital Territory 0200, Australia.
authors.forename: Y S
authors.initials: YS
authors.lastname: Kivshar
authors.affiliation: Department of Electrical and Systems Enginnering, Washington University, St Louis, Missouri 63130, USA.
authors.forename: L
authors.initials: L
authors.lastname: Yang
authors.affiliation: Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Imoto
authors.affiliation: Department of Electrical and Systems Enginnering, Washington University, St Louis, Missouri 63130, USA.
authors.forename: Ş K
authors.initials: ŞK
authors.lastname: Özdemir
authors.affiliation: Quantum Condensed Matter Research Group, Center for Emergent Matter Science, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.|Physics Department, University of Michigan, Ann Arbor, Michigan 48109-1040, USA.
authors.forename: F
authors.identifier: 0000-0003-3682-7432
authors.initials: F
authors.lastname: Nori