# Very Large and Reversible Stark Shift Tuning of Single Emitters in Layered Hexagonal Boron Nitride

## TL;DR

This study demonstrates a large, reversible Stark shift in single photon emitters within layered hexagonal boron nitride, enabling significant spectral tuning at room temperature for quantum photonics.

## Contribution

It introduces a method to achieve wide, reversible Stark shift tuning of SPEs in hBN using an AFM with a conductive tip, surpassing typical linewidths.

## Key findings

- Achieved a Stark shift of 5.5 nm at 670 nm wavelength with 20 V.
- Demonstrated reversible tuning of single photon emitters in hBN.
- Results facilitate practical spectral control in quantum photonic devices.

## Abstract

Combining solid state single photon emitters (SPE) with nanophotonic platforms is a key goal in integrated quantum photonics. In order to realize functionality in potentially scalable elements, suitable SPEs have to be bright, stable, and widely tunable at room temperature. In this work we show that selected SPEs embedded in a few layer hexagonal boron nitride (hBN) meet these demands. In order to show the wide tunability of these SPEs we employ an AFM with a conductive tip to apply an electrostatic field to individual hBN emitters sandwiched between the tip and an indium tin oxide coated glass slide. A very large and reversible Stark shift of $(5.5 \pm 3)\,$nm at a zero field wavelength of $670\,$nm was induced by applying just $20\,$V, which exceeds the typical resonance linewidths of nanodielectric and even nanoplasmonic resonators. Our results are important to further understand the physical origin of SPEs in hBN as well as for practical quantum photonic applications where wide spectral tuning and on/off resonance switching are required.