With the further miniaturization and integration of multi-dimensional optical information detection devices, polarization-sensitive photodetectors based on anisotropic low-dimension materials have attractive potential applications. However, the performance of these devices is restricted by intrinsic property of materials leading to a small polarization ratio of the detectors. Here, we construct a black phosphorus (BP) homojunction photodetector defined by ferroelectric domains with ultra-sensitive polarization photoresponse. With the modulation of ferroelectric field, the BP exhibits anisotropic dispersion changes, leading an increased photothermalelectric (PTE) current in the armchair (AC) direction. Moreover, the PN junction can promote the PTE current and accelerate carrier separation. As a result, the BP photodetector demonstrates an ultrahigh polarization ratio (PR) of 288 at 1450 nm incident light, a large photoresponsivity of 1.06 A/W, and a high detectivity of 1.27 × 1011 cmHz1/2W−1 at room temperature. This work reveals the great potential of BP in future polarized light detection.

New-generation infrared detectors call for higher operation temperature and polarization sensitivity. For traditional HgCdTe infrared detectors, the additional polarization optics and cryogenic cooling are necessary to achieve high-performance infrared polarization detection, while they can complicate this system and limit the integration. Here, a mixed-dimensional HgCdTe/black phosphorous van der Waals heterojunction photodiode is proposed for polarization-sensitive midwave infrared photodetection. Benefiting from van der Waals integration, type III broken-gap band alignment heterojunctions are achieved. Anisotropy optical properties of black phosphorous bring polarization sensitivity from visible light to midwave infrared without external optics. Our devices show an outstanding performance at room temperature without applied bias, with peak blackbody detectivity as high as 7.93 × 10 10 cm Hz 1/2 W −1 and average blackbody detectivity over 2.1 × 10 10 cm Hz 1/2 W −1 in midwave infrared region. This strategy offers a possible practical solution for next-generation infrared detector with high operation temperature, high performance, and multi-information acquisition.

The advent of low-dimensional materials with peculiar structure and superb band properties provides a new canonical form for the development of photodetectors. However, the limited exploitation of basic properties makes it difficult for devices to stand out. Here, we demonstrate a hybrid heterostructure with ultrathin vanadium dioxide film and molybdenum ditelluride nanoflake. Vanadium dioxide is a classical semiconductor with a narrow bandgap, a high temperature coefficient of resistance, and phase transformation. Molybdenum ditelluride, a typical two-dimensional material, is often used to construct optoelectronic devices. The heterostructure can realize three different functional modes: (i) the p–n junction exhibits ultrasensitive detection (450 nm–2 μm) with a dark current down to 0.2 pA and a response time of 17 μs, (ii) the Schottky junction works stably under extreme conditions such as a high temperature of 400 K, and (iii) the bolometer shows ultrabroad spectrum detection exceeding 10 μm. The flexible switching between the three modes makes the heterostructure a potential candidate for next-generation photodetectors from visible to longwave infrared radiation (LWIR). This type of photodetector combines versatile detection modes, shedding light on the hybrid application of novel and traditional materials, and is a prototype of advanced optoelectronic devices.

Indium antimony is a direct, narrow bandgap III–V semiconductor with ultrahigh carrier mobility and an attractive optoelectronic device candidate for use in the visible to infrared region. Here, an infrared (IR) photodetector based on high‐quality InSb nanosheets (NSs) is presented, which shows a clear photoresponse over a broad spectral range from visible (637 nm) to infrared (4.3 µm). Due to the high surface‐to‐volume ratio of nanostructured materials, defects on the sample surface can affect performance, which is a disadvantage for the ambipolar InSb photodetectors. To eliminate the impact of sample surface defects on performance, the surface of the sample is passivated with a ferroelectric film and the mechanism of increased sensitivity is explored. After covering the protective layer, the performance of the detector is greatly improved. The responsivity and detectivity of the photodetector are 311.5 AW−1 and 9.8 × 109 Jones, respectively. Compared with devices before passivation, the dark current is two orders of magnitude lower, the responsivity is 20 times higher, and the photoresponse time is shortened from seconds to the order of milliseconds. These InSb NSs with their outstanding photoelectric properties have great potential for developing next‐generation nanoscale optoelectronic devices.