Application
- Colloidal quantum dot molecules (CQDMs) are tiny switchable light sources: they form the smallest ever light source with switchable colors, unleashing a new era of color-tunable nano-devices.
- Colored light and its tunability are the basis of many essential technologies: from lighting, displays, fast optical fiber-communication networks, and more. Upon taking color-emitting semiconductors to the nanoscale forming quantum dots (Nobel prize in chemistry 2023), an effect called quantum confinement comes into play: changing the size of the quantum dot modifies the color of the emitted light. Thus, bright light sources can be obtained covering the entire visible spectrum. Due to the unique color tunability of such quantum dots, and their facile fabrication and manipulation using wet chemistry, they are already widely used in high-quality commercial displays, giving them excellent color quality along with significant energy-saving characteristics. However, to this day, achieving different colors (such as needed for the different RGB pixels) required the use of different quantum dots for each specific color, and dynamical switching between the different colors was not possible. This is an innovative solution to this problem.
Our Innovation
- Our invention consists of coupled quantum dot molecules (CQDM), with precise control over the composition and size of the QDs and the barrier in between them. In this manner, two quantum dots with the same or with different colors can be combined into a single artificial molecule system. (Ji, Banin et al, Nature Communications 10, 5401 (2019). https://www.nature.com/articles/s41467-019-13349-1)
- This invention of an “artificial molecule” made of two coupled quantum dots which are fused and coupled opens numerous possibilities for new light sources and display modalities. For example, a CQDM can be designed to emit light in two different colors such that fast and instantaneous color switching between them can be realized. The CQDM can be made such that one of its constituent QDs is tuned to emit “green” light, while the other “red” light. The emission of this new dual color emitting artificial molecule is sensitive to external voltage inducing an electric field: one polarity of the field induces emission of light from the “red” center, and switching the field to the other polarity, the color emission is switched instantaneously to “green”, and vice versa. This color-switching phenomenon is reversible and immediate, as it does not include any structural motion of the molecule. This allows to obtain each of the two colors, or any combination of them, simply by applying the appropriate voltage on the device (See illustration below).
- The electronic-quantum coupling between colloidal semiconductor quantum dots achieved by forming the coupled quantum dot molecules (CQDMs) is important for different optical, optoelectronic, display, bio-medical, quantum technologies, and photocatalytic applications.

A coupled quantum dot molecule, made of two coupled quantum dots each emitting light with distinct colors. applying an external voltage induces an electric field that can toggle the light emission from one side to the other, switching the emission color instantaneously while keeping the overall light intensity
These hold great potential for tuning their optical and electrical properties, making them applicable for various applications including light-emitting devices, elements in displays, photovoltaics, quantum light sources, biomedical sensors, and so on.
Advantages
Our technology offers several advantages that make it promising for a range of applications:
- Precise Control over Composition and Size: The ability to precisely control the composition and size of the barrier between coupled nanocrystal molecules, even possibly down to distances where hybridization and quantum coherences are taking place by the use of at least one core/shell quantum dot, allows for fine-tuning of the electronic and optical properties, enabling tailored designs for specific applications.
- Tunable Optical Properties: The ability to control and engineer the composition, shape, and size of the barrier influences the electronic transitions and emission characteristics of the QDs.
- Versatility for Various Combinations and Functionalities: The invention offers a set of novel colloidal nanocrystal structures with immense possibilities for different combinations and functionalities. This versatility opens up opportunities for diverse applications, ranging from electronics to biomedical sensors.
- Instantaneous Color Switching Effect was demonstratedin CQDMs under the application of an external electric field (Ossia, Banin et al. Nature Materials 22, 1210 (2023); https://www.nature.com/articles/s41563-023-01606-0; DOI: 10.1038/s41563-023-01606-0). The effect opens the path for innovative light sources, display modalities and sensors.
Opportunity
We are seeking collaboration with companies requiring emitting quantum dots, display companies interested in quantum dots for displays, companies requiring photocatalytic nanoparticles, or quantum technology companies interested in novel switchable quantum light sources.