A research team consisting of Professor Kyoung-Duck Park and Hyeongwoo Lee, an integrated PhD student, from the Department of Physics at Pohang University of Science and Technology (POSTECH) has pioneered an revolutionary technique in ultra-high-resolution spectroscopy. Their breakthrough marks the world’s first instance of electrically controlling polaritons — hybridized light-matter particles — at room temperature.
Polaritons are “half-light half-matter” hybrid particles, having each the characteristics of photons — particles of sunshine — and people of solid matter. Their unique characteristics exhibit properties distinct from each traditional photons and solid matter, unlocking the potential for next-generation materials, particularly in surpassing performance limitations of optical displays. Until now, the lack to electrically control polaritons at room temperature on a single particle level has hindered their business viability.
The research team has devised a novel method called “electric-field tip-enhanced strong coupling spectroscopy,” enabling ultra-high-resolution electrically controlled spectroscopy. This latest technique empowers the energetic manipulation of individual polariton particles at room temperature.
This method introduces a novel approach to measurement, integrating super-resolution microscopy previously invented by Prof. Kyoung-Duck Park ‘s team with ultra-precise electrical control. The resulting instrument not only facilitates stable generation of polariton in a particular physical state called strong coupling at room temperature but in addition allows for the manipulation of the colour and brightness of the sunshine emitted by the polariton particles through the usage of electric-field. Using polariton particles as a substitute of quantum dots, key materials of QLED televisions, offers a notable advantage. A single polariton particle can emit light in all colours with significantly enhanced brightness. This eliminates the necessity for 3 distinct sorts of quantum dots to provide red, green, and blue light individually. Furthermore, this property will be electrically controlled similar to traditional electronics. By way of academic significance, the team has successfully established and experimentally validated the quantum confined stark effect within the strong coupling regime, shedding light on a longstanding mystery in polariton particle research.
The team’s accomplishment holds profound significance because it marks a scientific breakthrough paving the trail for the following generation of research aimed toward creating diverse optoelectronic devices and optical components based on polariton technology. This breakthrough is poised to make a considerable contribution to industrial advancement, particularly in providing key source technology for the event of groundbreaking products throughout the optical display industry including ultra-bright and compact outdoor displays. Hyeongwoo Lee, the lead creator of the paper, emphasized the research’s importance, stating that it represents “a big discovery with the potential to drive advancements across quite a few fields including next-generation optical sensors, optical communications, and quantum photonic devices.”
The research utilized quantum dots fabricated by Professor Sohee Jeong’s team and Professor Jaehoon Lim’s team from Sungkyunkwan University. The theoretical model was crafted by Professor Alexander Efros of the Naval Research Laboratory while data evaluation was conducted by Professor Markus Raschke’s team from the University of Colorado and Professor Matthew Pelton’s team from the University of Maryland. Yeonjeong Koo, Jinhyuk Bae, Mingu Kang, Taeyoung Moon, and Huitae Joo from POSTECH’s Physics Department carried out the measurement work.
This research has been recently published in Physical Review Letters, a global physics journal, and was conducted with support from the Samsung Future Technology Incubation Program.
