Sign in

Michael Nielsen

@lasermike.bsky.social
278 followers 59 following 17 posts

Canadian undertaking spectroscopy and optoelectronics research Down Under. Senior Lecturer and Scientia Fellow at SPREE, UNSW Sydney www.aos-nielsen-group.com

PostsRepliesMedia
Reposted by Michael Nielsen
Tim Schmidt @schmidtim.bsky.social · 18/05/2026
Structural exciton localization drives efficient solid-state sensitized triplet fusion upconversion www.nature.com/articles/s41...
nature.com
Structural exciton localization drives efficient solid-state sensitized triplet fusion upconversion - Nature Photonics
An absolute photon upconversion efficiency of 8.2% is demonstrated using a liquid triplet fusion medium that behaves as solid on excitonic timescales. The findings may drive higher efficiencies in nan...
142
Michael Nielsen @lasermike.bsky.social · 08/03/2026
Have you ever wanted to send someone a message but didnt want an observer seeing you do it? Introducing thermoradiative signatureless communications (now published in LSA), an offshoot of our work on negative luminescence for night-time solar applications. www.nature.com/articles/s41...
nature.com
Balancing positive and negative luminescence for thermoradiative signatureless communications - Light: Science & Applications
We demonstrate covert transmission of data by rapidly modulating mid-infrared photodiodes, balancing forward and reverse bias luminescence. Only fast detectors resolve the signal; slow observers obser...
132
Reposted by Michael Nielsen
Nicholas Sloane @nicholassloane.bsky.social · 07/12/2025
Very excited for our new paper to come out in ACS Nano where we investigate room-temperature magneto-photoluminescence in 2D perovskite nanosheets! doi.org/10.1021/acsn...
doi.org
Between the Nanosheets: Enhancing Electron–Hole Exchange Interaction for Room-Temperature Magneto-Photoluminescence in Liquid-phase-exfoliated 2D Perovskite
Nanomaterials with a strong room-temperature optical response to magnetic fields are highly desirable for applications in sensing and photonics. Therefore, the ability to tune this response presents a...
041
Reposted by Michael Nielsen
Prashant Kamat @kamat.bsky.social · 29/08/2025
Latest work from @schmidtim.bsky.social Tayebjee and collaborators Singlet Fission c-Si Solar Cells: Beyond Tetracene | ACS Energy Letters pubs.acs.org/doi/10.1021/...
pubs.acs.org
Singlet Fission c-Si Solar Cells: Beyond Tetracene
Singlet fission photovoltaics enable the extraction of two electron–hole pairs from each higher-energy photon while leveraging a mature technology such as crystalline silicon (c-Si) as the underlying cell. Significant steps have been made in the development of singlet fission silicon photovoltaics, but all examples reported to date use tetracene as the singlet fission material. Tetracene is photochemically unstable and therefore unsuitable for commercial applications. Here we demonstrate singlet fission-derived triplet exciton transfer to c-Si from photochemically stable dipyrrolonaphthyridinedione (DPND) derivatives, with a thin layer of tin oxide as the passivation layer. An overlayer of poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS) was found to improve interface passivation further. These observations demonstrate that singlet fission photovoltaic devices can be made using stable and commercially viable materials.
0103
Michael Nielsen @lasermike.bsky.social · 03/06/2025
Finally published in @natnano.nature.com, this work shows how A-site cation in perovskites influences dynamic nanodomains, fleeting pockets of tilted octahedra, lurking in the lattice. Nanoscale crystallography driving macroscopic performance! www.nature.com/articles/s41...
nature.com
Dynamic nanodomains dictate macroscopic properties in lead halide perovskites - Nature Nanotechnology
Dynamic nanodomains in lead halide perovskites, dictated by A-site cations, crucially affect the optoelectronic properties by modulating electronic disorder and consequently enabling better solar cell...
162
Michael Nielsen @lasermike.bsky.social · 31/10/2023
Congratulations on passing the PhD to Dr Abhinav Sharma, who I had the pleasure of supervising these last few years. He leaves us soon for greener pastures in Germany, but leaves behind a great read: unsworks.unsw.edu.au/entities/pub...
050