Single quantum dot spectroscopy using a fiber taper waveguide near-field optic

TL;DR

This paper demonstrates a method for performing photoluminescence spectroscopy on single InAs quantum dots at cryogenic temperatures using a fiber taper waveguide as a near-field optic, achieving spatial resolution and collection efficiency measurements.

Contribution

It introduces a fiber taper waveguide technique for near-field optical spectroscopy of single quantum dots, enabling spatially-resolved measurements and efficiency estimation.

Findings

Collection efficiency estimated at 0.1%

Achieved ~600 nm spatial resolution

Performed spectroscopy at ~14 K

Abstract

Photoluminescence spectroscopy of single InAs quantum dots at cryogenic temperatures (~14 K) is performed using a micron-scale optical fiber taper waveguide as a near-field optic. The measured collection efficiency of quantum dot spontaneous emission into the fundamental guided mode of the fiber taper is estimated at 0.1%, and spatially-resolved measurements with ~600 nm resolution are obtained by varying the taper position with respect to the sample and using the fiber taper for both the pump and collection channels.