Polarization-sensitive and wide-spectrum photovoltaic detector based on quasi-1D ZrGeTe4 nanoribbon

Low-dimensional semiconductors with in-plane anisotropy and narrow bandgap have been extensively applied to polarized detection in the near-infrared (NIR) region. However, the narrow bandgap can cause noise owing to the high dark current in photodetectors. This article reports quasi-1D ZrGeTe4 nanoribbon-based photodetectors with low dark current and broadband polarization detection. The photodetector was fabricated by evaporating 50-nm-thick Au electrodes on a ZrGeTe4 nanoribbon. Benefiting from the photovoltaic characteristics in the ZrGeTe4 nanoribbon and Au electrodes, these photodetectors can operate without bias voltage, with decreased dark current, and improved device performance. Furthermore, the quasi-1D ZrGeTe4 nanoribbon-based photodetectors demonstrate a polarization sensitivity in a broadband from visible (VIS) to the NIR region, such as a high photoresponsivity of 625.65 mA W-1, large external quantum efficiency of 145.9% at 532 nm, and photocurrent anisotropy ratio of 2.04 at 1064 nm. They exhibit a novel perpendicular optical reversal of 90 degrees in polarization-sensitive photodetection, angle-resolved absorption spectra, and azimuth-dependent reflectance difference microscopy (ADRDM) from VIS to the NIR region, as opposed to other nanoribbon-based polarization-sensitive photodetectors. This work paves the way for utilizing photovoltaic photodetectors based on low-dimensional materials for broad-spectrum polarized photodetection.