Speaker: Pradeep Kumar
Affiliation: University of Queensland


Waveguide quantum electrodynamics is a nascent field of quantum optics that describes the interaction between quantum emitters and photons in a 1D radiation channel. Recently, several novel regimes of light-matter interaction have been identified by embedding qubits in waveguides that support photonic bandgaps [1]. When the energy of the qubits lies close to the band edge, qubit-photon bound states are predicted to emerge. The photonic part of this bound state wavefunction is exponentially localised around the qubit position and extends to the ends of the waveguide [1, 2]. In this talk I will present experimental results that demonstrate the in-situ frequency tunable characteristics of these bound states such as the localization length, interaction strength between multiple bound states and the chirality of photonic wavefunctions and thereby preserving the special organisation of the qubits in the waveguide [3].

[1] Interacting Qubit-Photon Bound States with Superconducting Circuits, Phys. Rev. X 9, 011021 (2019).
[2] Bound states in microwave QED: Crossover from waveguide to cavity regime, arXiv:2208.00558 (2022)

[3] Qubit-controlled directional edge states in waveguide QED, arXiv:2212.00108 (2022)

About Physics Seminars

The weekly Physics Seminar series focuses on a broad range of physics research within SMP, along with frequent presentations from visiting researchers. Seminars are usually scheduled for 1.00pm on Tuesdays.

The talks are typically more specialised than a colloquium but are often attended by staff and PhD students across a broad range of areas. Speakers are thus encouraged to include introductory material in the talks.

All SMP researchers and HDR students are encouraged to speak. Please email Lewis Williamson to register your interest.

The seminars are open so there is no need to register your attendance.


Physics Annexe (06)
407 (and via Zoom: https://uqz.zoom.us/j/94116861984)