Solution-phase sample-averaged single-particle spectroscopy of quantum emitters with femtosecond resolution

Jiaojian Shi; Yuejun Shen; Feng Pan; Weiwei Sun; Anudeep Mangu; Cindy Shi; Amy McKeown-Green; Parivash Moradifar; Moungi G Bawendi; W E Moerner; Jennifer A Dionne; Fang Liu; Aaron M Lindenberg

doi:10.1038/s41563-024-01855-7

Solution-phase sample-averaged single-particle spectroscopy of quantum emitters with femtosecond resolution

Nat Mater. 2024 Apr 8. doi: 10.1038/s41563-024-01855-7. Online ahead of print.

Authors

Jiaojian Shi^#^{1

2}, Yuejun Shen^#^{1

2}, Feng Pan^#¹, Weiwei Sun³, Anudeep Mangu^{1

2}, Cindy Shi¹, Amy McKeown-Green⁴, Parivash Moradifar¹, Moungi G Bawendi³, W E Moerner⁴, Jennifer A Dionne^{1

5}, Fang Liu⁴, Aaron M Lindenberg^{6

7

8}

Affiliations

¹ Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
² Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
³ Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
⁴ Department of Chemistry, Stanford University, Stanford, CA, USA.
⁵ Department of Radiology, Stanford University, Stanford, CA, USA.
⁶ Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA. aaronl@stanford.edu.
⁷ Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. aaronl@stanford.edu.
⁸ Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA. aaronl@stanford.edu.

^# Contributed equally.

PMID: 38589542
DOI: 10.1038/s41563-024-01855-7

Abstract

The development of many quantum optical technologies depends on the availability of single quantum emitters with near-perfect coherence. Systematic improvement is limited by a lack of understanding of the microscopic energy flow at the single-emitter level and ultrafast timescales. Here we utilize a combination of fluorescence correlation spectroscopy and ultrafast spectroscopy to capture the sample-averaged dynamics of defects with single-particle sensitivity. We employ this approach to study heterogeneous emitters in two-dimensional hexagonal boron nitride. From milliseconds to nanoseconds, the translational, shelving, rotational and antibunching features are disentangled in time, which quantifies the normalized two-photon emission quantum yield. Leveraging the femtosecond resolution of this technique, we visualize electron-phonon coupling and discover the acceleration of polaronic formation on multi-electron excitation. Corroborated with theory, this translates to the photon fidelity characterization of cascaded emission efficiency and decoherence time. Our work provides a framework for ultrafast spectroscopy in heterogeneous emitters, opening new avenues of extreme-scale characterization for quantum applications.

Abstract

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