Soft and Biological Quantum Light Sources

Quantum light sources generate light with distinct quantum features, most frequently single photons or photon pairs, essential in applications such as quantum communication, quantum computing, and quantum metrology. The most common way of generating (entangled) photon pairs is spontaneous parametric down-conversion (SPDC), where a nonlinear crystal is used to split a single incoming photon into two photons. In recent decades, no revolutionary advances have been made regarding these nonlinear materials. In fact, lithium niobate is still one of the best and one of the most used nonlinear crystals for the generation of photon pairs more than 50 years after it was used for the first demonstration of SPDC.

In this webinar hosted by the Quantum Applications in Biomedicine and Material Chemistry Technical Group, Matjaž Humar will discuss the recent first-time demonstration of the generation of entangled photons from ferroelectric nematic liquid crystals (FNLCs). This is also the first demonstration of SPDC in any organic material. The conversion efficiency is on par with the best nonlinear crystals available today, with the added benefit of tailoring and tuning the output of the source by electric field.

Further, Humar will present single-photon emission from hBN color centers embedded inside live cells and their application to uniquely tag virtually an unlimited number of cells. This barcoding technique has many advantages, including ease of production, biocompatibility and biodegradability, emission stability, no photobleaching, small size, and a huge number of unique barcodes.

What You Will Learn:
• Alternative ways of generating entangled photons in organic material
• Unique application of single photon sources for tagging live cells

Who Should Attend:
• Early Career Professionals
• Students

About the Presenter: Matjaz Humar from Jožef Stefan Institute and University of Ljubljana

Dr. Matjaž Humar is an Assistant Professor at the University of Ljubljana's Faculty of Mathematics and Physics and the Head of the Lab for biophotonics, soft photonics and quantum optics at the Jožef Stefan Institute in Ljubljana, Slovenia. He earned his PhD in 2012 from the Jožef Stefan International Postgraduate School, focusing on liquid-crystal microdroplets as optical microresonators and lasers.

Dr. Humar's research lies at the intersection of soft matter physics, photonics, and biomedicine. His work includes pioneering developments in intracellular microlasers, whispering-gallery-mode sensors, and edible lasers for applications in food and pharmaceutical quality control.

His contributions have been recognized with several accolades, including the 2022 Blinc Award for early-career physicists and the 2023 Uroš Seljak Award for mentorship. Notably, an asteroid was named after him—Matjazhumar (17201)—in honor of his achievements.