Prof. Eli Kapon
Institute of Physics Ecole Polytechnique Fédérale de Lausanne (EPFL) , Switzerland
Development of means for manipulating quantum states of light on a chip constitutes an important emerging platform for quantum information technologies. Attractive techniques for producing and controlling such states of light employ photon emission from semiconductor quantum dots (QDs) and their manipulation using photonic crystal (PhC) structures. This talk first reviews the nanotechnology of producing site-controlled QD systems via growth on patterned substrates, and their integration with PhC membrane cavities and waveguides. It then presents recent studies on basic cavity-QED and single-photon routing on a chip using such integrated systems. The fabrication of the structures begins with growth of InGaAs/GaAs QDs emitting in the ~900nm wavelength range inside pyramidal pits produced at prescribed locations on (111)B-oriented GaAs substrates using electron beam lithography, etching and organometallic vapor phase epitaxy [1]. Various PhC cavities and waveguides are then nanofabricated around the QDs with positioning precision as good as ~20nm [2]. The QDs are photo-excited at low temperatures and the photons emitted into various PhC modes are analyzed using optical spectroscopy. New features of the Purcell effect related to quantum interference among confined and radiation modes are unraveled using such structures [3]. Integration of the QDs with more complex PhC structures comprising coupled cavities and waveguides for single-photon on-chip routing are also presented and discussed [4].
[1] A. Surrente, et al., Nano Research 9, (11), 3279-3290 (2016).
[2] C. Jarlov, et al., Phys. Rev. Lett. 117, 076801 (2016).
[3] A. Lyasota, et al., Phys. Rev. X 12, 021042 (2022).
[4] Y. Yu, et al., Optica 8, 1605 (2021).