Polarized light produced by magne-assembled nanoarrays

Linear optical polarizers are passive components that selectively transmit photons with electric fields parallel to the transmission axis (s-polarization) and block the transmission of the electromagnetic field in the orthogonal direction (p-polarization). Polarizers are crucial for various optical systems and extensively used in applications ranging from imaging and liquid crystal displays (LCDs). Thus, the development of effective polarized light-emitting sources is an active area of research, and may serve to increase the optical efficiency of the LCDs.

In a recent paper, Can Uran et al. demonstrated the emission of highly polarized light in coupled thin films of colloidal quantum dots (QDs) and magnetically aligned multi-segmented nanowires (NWs). These NWs consist of ferromagnetic (Ni) parts that assemble into well-organized arrays under externally applied magnetic field. In-template synthesis of these NWs together with their magnetic field assisted alignment allows the rapid and low-cost fabrication of massive numbers of highly parallel NWs over large area thin films.

The assembly can be triggered by centimeter-sized, commercially available magnets, which makes this approach a versatile tool for the alignment of NWs containing ferromagnetic elements, either on a surface or within a host medium. Unlike competing techniques, the method does not require surface functionalization or a pre-defined electrode, operating solely based on magnetic alignment.

This work has been published in Applied Physics Letters. Samsung, Korea also showed great interest in this research, and has applied for the Korean patent of the team’s proof-of-concept device.

