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arXiv · 2504.15258

Broadband Fourier transform spectroscopy of quantum emitters photoluminescence with sub-nanosecond temporal resolution

Issam Belgacem·Pasquale Cilibrizzi·Muhammad Junaid Arshad·Daniel White·Malte Kroj·Christiaan Bekker·Margherita Mazzera·Brian D. Gerardot·Angelo C. Frangeskou·Gavin W. Morley·Nguyen Tien Son·Jawad Ul-Hassan·Takeshi Ohshima·Hiroshi Abe·Lorenzo Vinco·Dario Polli·Giulio Cerullo·Cristian Bonato
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Abstract

The spectral characterization of quantum emitter luminescence over broad wavelength ranges and fast timescales is important for applications ranging from biophysics to quantum technologies. Here we present the application of time-domain Fourier transform spectroscopy, based on a compact and stable birefringent interferometer coupled to low-dark-count superconducting single-photon detectors, to the study of quantum emitters. We experimentally demonstrate that the system enables spectroscopy of quantum emitters over a broad wavelength interval from the near-infrared to the telecom range, where grating-based spectrometers coupled to InGaAs cameras are typically noisy and inefficient. We further show that the high temporal resolution of single-photon detectors, which can be on the order of tens of picoseconds, enables the monitoring of spin-dependent spectral changes on sub-nanosecond timescales.

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Issam Belgacem, Pasquale Cilibrizzi, Muhammad Junaid Arshad, Daniel White, Malte Kroj, Christiaan Bekker, Margherita Mazzera, Brian D. Gerardot, Angelo C. Frangeskou, Gavin W. Morley, Nguyen Tien Son, Jawad Ul-Hassan, Takeshi Ohshima, Hiroshi Abe, Lorenzo Vinco, Dario Polli, Giulio Cerullo, Cristian Bonato. 2025-04-21. Broadband Fourier transform spectroscopy of quantum emitters photoluminescence with sub-nanosecond temporal resolution. https://arxiv.org/abs/2504.15258

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