On-Chip Electrostatic Actuation of a Photonic Wire Antenna Embedding Quantum Dots

Abstract

A photonic wire antenna embedding individual quantum dots (QDs) constitutes a promising platform for both quantum photonics and hybrid nanomechanics. We demonstrate here an integrated device in which on-chip electrodes can apply a static or oscillating bending force to the upper part of the wire. In the static regime, we achieve control over the bending direction and apply at will tensile or compressive mechanical stress on any QD. This results in a blue shift or red shift of their emission, with direct application to the realization of broadly tunable sources of quantum light. As a first illustration of operation in the dynamic regime, we excite the wire fundamental flexural mode and use the QD emission to detect the mechanical vibration. With an estimated operation bandwidth in the GHz range, electrostatic actuation opens appealing perspectives for the exploration of QD-nanowire hybrid mechanics with high-frequency vibrational modes.

High-Order Nanowire Resonances for High-Frequency, Large-Coupling-Strength Quantum Dot Hybrid Nanomechanics

“…Mechanical drive is provided by a recently developed on-chip electrostatic actuation technique. 33 We show here that the on-chip electrodes generate a 3D force field that can excite flexural and longitudinal vibration modes. Wire vibrations are detected optically by measuring the QD photoluminescence spectrum.…”

“…In this work, we explore the high-order mechanical resonances of a conical GaAs nanowire that embeds a few self-assembled InAs QDs. Mechanical drive is provided by a recently developed on-chip electrostatic actuation technique . We show here that the on-chip electrodes generate a 3D force field that can excite flexural and longitudinal vibration modes.…”

“…The device under investigation is schematized in Figure a, and the scanning electron micrographs are shown in the Supporting Information. As detailed in ref , fabrication starts with the growth of a planar structure by molecular beam epitaxy, followed by a flip-chip and top-down processing that includes a carefully optimized dry etching step. The mechanical oscillator is a 16.4 μm-long conical nanowire made of GaAs, which is oriented along the “vertical” z = [001] crystallographic direction.…”

“…The AC part, which drives wire vibrations, is dominated by a term that oscillates at ω with an amplitude proportional to product V dc V ac . Compared to ref , the nanowire is offset from the center of the needle electrodes. Such an asymmetric location makes it possible to excite the various vibrational modes supported by the nanowire.…”

“…37 Mechanical vibrations are driven by applying an electrostatic force on the nanowire thanks to three on-chip electrodes. 33 As shown in Figure 1a, one of the top needle electrodes is biased at potential V(t) = V dc + V ac cos(ωt), whereas the other needle electrode and the bottom gold plane are grounded. We choose here a negative DC bias in order to limit leakage currents and operate the device with |V ac | ≪ |V dc |.…”