Abstract Smart windows are energy‐efficient windows whose optical transparency can be switched between highly transparent and opaque states in response to incident solar illumination. Transparent and conductive metal nanomesh (NM) films are promising candidates for thermochromic smart windows due to their excellent thermal conductivity, high optical transparency at near infrared wavelengths, and outstanding stability. In this study, ZnO/Au/Al2O3NM films with periodicities of 200 and 370 nm are reported. The ZnO/Au/Al2O3NM film with a 370 nm periodicity exhibits a transmittance over 90% at 550 nm and sheet resistance lower than 20 Ω sq−1. Based on a standard figure of merit, this structure outperforms current state‐of‐the‐art NM films. Here, the integration of ZnO/Au/Al2O3NM films into a thermochromic perovskite smart window is also demonstrated. The transparency of the smart window structure is manipulated by transient resistive heating to trigger the thermochromic transition to the opaque state, which can be then maintained solely by 1‐sun, AM 1.5 G illumination. This climate‐adaptive, low power‐activated, and fast‐switching smart window structure opens new pathways toward its practical application in the real world.
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Layered metals as polarized transparent conductors
Abstract The quest to improve transparent conductors balances two key goals: increasing electrical conductivity and increasing optical transparency. To improve both simultaneously is hindered by the physical limitation that good metals with high electrical conductivity have large carrier densities that push the plasma edge into the ultra-violet range. Technological solutions reflect this trade-off, achieving the desired transparencies only by reducing the conductor thickness or carrier density at the expense of a lower conductance. Here we demonstrate that highly anisotropic crystalline conductors offer an alternative solution, avoiding this compromise by separating the directions of conduction and transmission. We demonstrate that slabs of the layered oxides Sr2RuO4and Tl2Ba2CuO6+δare optically transparent even at macroscopic thicknesses >2 μm for c-axis polarized light. Underlying this observation is the fabrication of out-of-plane slabs by focused ion beam milling. This work provides a glimpse into future technologies, such as highly polarized and addressable optical screens.
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- Award ID(s):
- 2003343
- PAR ID:
- 10484819
- Publisher / Repository:
- Nature
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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