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DOE OSTI · 3029256

High‐Temperature Single‐Photon Emission From Covalently Functionalized van der Waals Heterostructures

Gavin, S. Carin [Northwestern University, Evanston, IL (United States)] (ORCID:0000000165852798)·Chuang, Hsun‐Jen [United States Naval Research Laboratory, Washington D.C. (United States)]·Dasgupta, Anushka [Northwestern University, Evanston, IL (United States)]·Kar, Moumita [Northwestern University, Evanston, IL (United States)]·McCreary, Kathleen M. [United States Naval Research Laboratory, Washington D.C. (United States)]·Lee, Sung‐Joon [United States Naval Research Laboratory, Washington D.C. (United States)]·Utama, M. Iqbal Bakti [Northwestern University, Evanston, IL (United States)]·Zhou, Chunxi [Northwestern University, Evanston, IL (United States)]·Li, Xiangzhi [Stevens Institute of Technology Hoboken, NJ (United States)]·Schatz, George C. [Northwestern University, Evanston, IL (United States)]·Marks, Tobin J. [Northwestern University, Evanston, IL (United States)]·Hersam, Mark C. [Northwestern University, Evanston, IL (United States)]·Jonker, Berend T. [United States Naval Research Laboratory, Washington D.C. (United States)]·Stern, Nathaniel P. [Northwestern University, Evanston, IL (United States)] (ORCID:0000000289033516)
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Abstract

Two-dimensional (2D) transition metal dichalcogenides (TMDs) such as tungsten diselenide (WSe 2 ) are attractive nanomaterials for quantum information applications due to single-photon emission (SPE) from intrinsic atomic defects. Defect and strain engineering techniques have been developed to produce high purity, deterministically placed SPE in WSe 2 . However, a major challenge in the application of these techniques is the low temperature required to observe defect-bound TMD exciton emission, typically limiting SPE to T < 30 K. SPE at higher temperatures either loses purity or requires integration into complex devices such as optical cavities. Here, 2D heterostructure engineering and molecular functionalization are combined to achieve high purity (>90%) SPE in strained WSe 2 persisting to over T = 90 K. Covalent diazonium functionalization of graphite in layered WSe 2 /graphite heterostructures maintains high purity up to T = 90 K and single-photon source integrity up to T = 115 K. This method preserves the best qualities of SPE from WSe 2 while increasing working temperature to more than three times the typical range. This work demonstrates the versatility of surface functionalization and heterostructure design to synergistically improve the properties of quantum emission and offers new insights into the phenomenon of SPE from 2D materials.

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2D materialscovalent functionalizationdefect emissiondiazoniumquantum emittertransition metal dichalcogenidestungsten diselenide

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Gavin, S. Carin [Northwestern University, Evanston, IL (United States)] (ORCID:0000000165852798), Chuang, Hsun‐Jen [United States Naval Research Laboratory, Washington D.C. (United States)], Dasgupta, Anushka [Northwestern University, Evanston, IL (United States)], Kar, Moumita [Northwestern University, Evanston, IL (United States)], McCreary, Kathleen M. [United States Naval Research Laboratory, Washington D.C. (United States)], Lee, Sung‐Joon [United States Naval Research Laboratory, Washington D.C. (United States)], Utama, M. Iqbal Bakti [Northwestern University, Evanston, IL (United States)], Zhou, Chunxi [Northwestern University, Evanston, IL (United States)], Li, Xiangzhi [Stevens Institute of Technology Hoboken, NJ (United States)], Schatz, George C. [Northwestern University, Evanston, IL (United States)], Marks, Tobin J. [Northwestern University, Evanston, IL (United States)], Hersam, Mark C. [Northwestern University, Evanston, IL (United States)], Jonker, Berend T. [United States Naval Research Laboratory, Washington D.C. (United States)], Stern, Nathaniel P. [Northwestern University, Evanston, IL (United States)] (ORCID:0000000289033516). 2025-10-07. High‐Temperature Single‐Photon Emission From Covalently Functionalized van der Waals Heterostructures. https://doi.org/10.1002/advs.202511319

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