Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Magnetically Actuated Dynamic Iridescence Inspired by the Neon Tetra

Inspired by the tropical fish neon tetra, we report a mechanism to achieve dynamic iridescence that can be magnetically tuned. This approach is based on the tilting of periodic photonic nanostructures, as opposed to the more common strain-induced color tuning. In this method, a periodic array of magnetic nanopillars serves as a template to guide the assembly of iron oxide nanoparticles when magnetized in a liquid environment. The periodic local fields induced by the magnetic template anchor the assembled particle columns, allowing the structure to tilt about the base when the angle of the applied field is changed. This effect emulates a microscopic “Venetian blind” and results in dynamic optical properties through structural coloration that is tunable in real time. The fabricated prototype demonstrates tunable reflectance spectra with peak wavelength shift from 528 to 720 nm. The magnetic actuation mechanism is reversible and has a fast response time around 0.3 s. This structure can be implemented on an arbitrary surface as dynamic camouflage, iridescent display, and tunable photonic elements, as well as in other applications such as active fluidic devices and particle manipulation

Active Periodic Magnetic Nanostructures with High Aspect Ratio and Ultrahigh Pillar Density

Magnetically actuated micro/nanoscale pillars have attracted significant research interest recently because of their dynamic properties. These structures can be used for various applications, such as dry adhesion, cell manipulation, and sensors or actuators in microfluidics. Magnetically actuated structures can be fabricated by mixing magnetic particles and polymers to yield a favorable combination of magnetic permeability and mechanical compliance. However, the pillar density of demonstrated structures is relatively low, which limits the potential applications in active surface manipulation of microscale objects. Here, we demonstrate active periodic nanostructures with a pillar density of 0.25 pillar/μm2, which is the highest density for magnetically actuated pillars so far. Having a structure period of 2 μm, diameter of 600 nm, and high aspect ratio of up to 11, this structure can be magnetically actuated with a displacement of up to 200 nm. The behaviors of the pillars under various cyclic actuation modes have been characterized, demonstrating that the actuation can be well controlled. This work can find potential applications in particle manipulation and tunable photonic elements

Active Periodic Magnetic Nanostructures with High Aspect Ratio and Ultrahigh Pillar Density

Magnetically actuated micro/nanoscale pillars have attracted significant research interest recently because of their dynamic properties. These structures can be used for various applications, such as dry adhesion, cell manipulation, and sensors or actuators in microfluidics. Magnetically actuated structures can be fabricated by mixing magnetic particles and polymers to yield a favorable combination of magnetic permeability and mechanical compliance. However, the pillar density of demonstrated structures is relatively low, which limits the potential applications in active surface manipulation of microscale objects. Here, we demonstrate active periodic nanostructures with a pillar density of 0.25 pillar/μm2, which is the highest density for magnetically actuated pillars so far. Having a structure period of 2 μm, diameter of 600 nm, and high aspect ratio of up to 11, this structure can be magnetically actuated with a displacement of up to 200 nm. The behaviors of the pillars under various cyclic actuation modes have been characterized, demonstrating that the actuation can be well controlled. This work can find potential applications in particle manipulation and tunable photonic elements