Gaining Control of Spin in Optoelectronics

By combining a chiral semiconductor with an LED, scientists controlled the orientation of electron spin.

December 16, 2025

A spin-LED stack consisting of a chiral semiconductor layer that controls the orientation of electron spins to emit circularly polarized light.

Image courtesy of Alfred Hicks, National Renewable Energy Laboratory.

The Science

Light emitting diodes (LEDs) work by converting electric current in a way that produces visible light. Current optoelectronic devices (electric devices that interact with light), like LEDs, control only light and charge. They do not control the spin of electrons. However, being able to control electron spins could help us improve microelectronics. An electron’s spin orientation can be either “up” or “down.” Ways to control spin include cooling the material to extremely low temperatures, applying an external magnetic field, or using magnetic materials. Here, the scientists controlled the interconversion between light, charge, and spin, at room temperature and without a magnetic field.

The Impact

For this new type of LED, scientists combined a traditional LED with a chiral semiconductor. This discovery takes advantage of the property of chirality. This property occurs in objects that can be distinguished from their mirror images, such as human hands. People’s left and right hands are mirror images. When one hand is on top of the other, they are not superimposable. In this research, the “left-handed” chiral system allowed the transport of electrons with “up” spins and blocked the “down” spins, and vice versa. This is similar to what happens when shaking hands, i.e. a left hand only can shake a right hand and vice versus. The chiral semiconductor effectively filters the electron spin. As a result, it controls the orientation of the spin. By gaining control over spin, scientists can transform optoelectronics into opto-spintronics. These devices could be used for enhanced LEDs, solar cells, and telecommunications lasers. They could also potentially enable quantum-based optical computing and sensing.

Summary

The scientists created a new polarized LED that emits spin-controlled photons at room temperature. They did so without using magnetic fields or ferromagnetic contacts. They achieved this by coupling a chiral halide perovskite semiconductor with an ‘off the shelf’ III-V LED. This change introduced spin control through the chirality-induced spin selectivity effect. The chiral layer produces electrons with one type of spin orientation. When the desired electrons pass into the non-chiral light-emitting layer, the layer transfers the spin of the electrons to the spin of the photons, instead of random polarization. The spin of the photons is termed circular polarized light. The degree of circular polarization was over five times higher than the previously reported value that used a different emitter layer.

These findings demonstrate that chiral semiconductors can transform existing semiconductors into ones that can also control spin. The control of electron spin in semiconductor structures operating at room temperature and without external magnetic fields will enable a broader range of new optoelectronic effects and functionality.

Contact

Matthew C. Beard
National Renewable Energy Laboratory
Senior Research Fellow
Matt.Beard@nrel.gov

Funding

This work was supported as part of the Center for Hybrid Organic-Inorganic Semiconductors for Energy (CHOISE), an Energy Frontier Research Center financed by the Office of Basic Energy Sciences, Office of Science in the U.S. Department of Energy (DOE). Support for structural and microscopy characterization and LED characterization was provided by a Laboratory Directed Research and Development project financed by NREL. This work was performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the DOE Office of Science by Los Alamos National Laboratory and Sandia National Laboratories. A. Wibowo at MicroLink Devices grew the AlGaInP LED device structures with funding from the DOE Office of Energy Efficiency and Renewable Energy, Buildings Technologies Office.

Publications

Hautzinger, M.P., et al., Room-temperature spin injection across a chiral perovskite/III–V interface. Nature (2024). [DOI: 10.1038/s41586-024-07560-4]

Kim, Y.-H. et al., Chiral-induced spin selectivity enables a room-temperature spin light-emitting diode. Science 371, 1129 (2021). [DOI: 10.1126/science.abf5291]