Electrical tuning of quantum light emitters in hBN for free space and telecom optical bands

Akbar Basha Dhu-Al Shaik; Penchalaiah Palla; David Jenkins

doi:10.1038/s41598-024-51504-x

Electrical tuning of quantum light emitters in hBN for free space and telecom optical bands

Sci Rep. 2024 Jan 8;14(1):811. doi: 10.1038/s41598-024-51504-x.

Authors

Akbar Basha Dhu-Al Shaik¹, Penchalaiah Palla², David Jenkins³

Affiliations

¹ Department of Micro and Nanoelectronics, School of Electronics Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
² Department of Micro and Nanoelectronics, School of Electronics Engineering, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India. penchalaiah.palla@vit.ac.in.
³ School of Engineering, Computing and Mathematics, Faculty of Science and Engineering, University of Plymouth, Plymouth, England, UK.

Abstract

Quantum light emitters (also known as single photon emitters) are known to be the heart of quantum information technologies. Irrespective of possessing ideal single photon emitter properties, quantum emitters in 2-D hBN defect structures, exhibit constrained quantum light emission within the 300-700 nm range. However, this emission range cannot fully satisfy the needs of an efficient quantum communication applications such as quantum key distribution (QKD), which demands the quantum light emission in fiber optic telecom wavelength bands (from 1260 to 1625 nm) and the free space optical (FSO) (UV-C-solar blind band-100 to 280 nm) wavelength ranges. Hence, there is a necessity to tune the quantum light emission into these two bands. However, the most promising technique to tune the quantum light emitters in hBN here, is still a matter of debate and till date there is no experimental and theoretical assurances. Hence, this work will focus on one of the most promising simple techniques known as Stark electrical tuning of the quantum light emission of hBN defect structures (N_BV_N, V_B, C_B, C_BV_N, C_BC_N, C_BC_NC_BC_N complex, and V_BO₂). These hBN defects are designed and sandwiched as metal/graphene/hBN defect structure/graphene/metal heterostructure and electrically tuned towards FSO and fiber optic bands (tuning range from UV-C to O-band IR region) region, using constrained DFT computations. The external electric field predicted to yield an atomic bond angle tilt associated with this point defect structure creates out-of-plane dipole moments, enabling the tuning of quantum emission. This electrical tuning technique leads to a simple passive photonic component which enables easier compatibility with quantum circuits and it is found to be one of the perfect alternative solutions, which does not require much external hardware setup to implement as compared to earlier published strain induced tuning experiments.