Room‐temperature‐operating highly sensitive mid‐wavelength infrared (MWIR) photodetectors are utilized in a large number of important applications, including night vision, communications, and optical radar. Many previous studies have demonstrated uncooled MWIR photodetectors using 2D narrow‐bandgap semiconductors. To date, most of these works have utilized atomically thin flakes, simple van der Waals (vdW) heterostructures, or atomically thin p–n junctions as absorbers, which have difficulty in meeting the requirements for state‐of‐the‐art MWIR photodetectors with a blackbody response. Here, a fully depleted self‐aligned MoS2‐BP‐MoS2 vdW heterostructure sandwiched between two electrodes is reported. This new type of photodetector exhibits competitive performance, including a high blackbody peak photoresponsivity up to 0.77 A W−1 and low noise‐equivalent power of 2.0 × 10−14 W Hz−1/2, in the MWIR region. A peak specific detectivity of 8.61 × 1010 cm Hz1/2 W−1 under blackbody radiation is achieved at room temperature in the MWIR region. Importantly, the effective detection range of the device is twice that of state‐of‐the‐art MWIR photodetectors. Furthermore, the device presents an ultrafast response of ≈4 µs both in the visible and short‐wavelength infrared bands. These results provide an ideal platform for realizing broadband and highly sensitive room‐temperature MWIR photodetectors.

The discovery of 2D ferromagnetic (FM) van der Waals (vdW) semiconductors with narrow bandgap and p‐type transport behavior makes them promising for infrared photodetection. Here, a 2D vdW heterodiode uncooled long‐wave infrared (LWIR) photodetector by stacking a p‐type 2D FM material CrSiTe3 on top of an n‐type transition metal dichalcogenides (TMDs) MoS2 is reported. A good rectification ratio >102 and an ultra‐broadband photoresponse from 0.52 to 10.6 μm are demonstrated. The photoresponsivity of up to 20.7 A W−1 and the external quantum efficiency (EQE) of up to 4031.7% are obtained under a 1310 nm laser at a −1 V bias in ambient, which indicates that these CrSiTe3–MoS2 p–n junction devices have a good photovoltaic response. Meanwhile, the photovoltaic responsivity up to 0.15 A W−1, EQE up to 29.7%, and fast response with a decay time of 2.8 μs at 637 nm are demonstrated. In addition, the room temperature mid‐wave infrared (MWIR) specific detectivity and LWIR specific detectivity of CrSiTe3–MoS2 is 6.1 × 109 cm Hz1/2 W−1 and 1.93 × 109 cm Hz1/2 W−1, respectively. These observations open up possibilities for developing high‐sensitive infrared detection based on the valley optical selection rule and LWIR image technology.

Ambient temperature long‐wavelength infrared (LWIR) photodetection has many critical applications ranging from thermal imaging and optical communications to night vision cameras. Currently, high performance, low cost, air stability, and ultra‐broadband response still constitute challenges. Here, the study demonstrates a high‐performance uncooled LWIR photodetector using 2D hexagonal α‐Fe2O3 single crystal nanoflakes, which are synthesized via chemical vapor deposition. The 2D α‐Fe2O3 photodetector realizes high specific detectivity (D*) of 3.28×109 cmHz1/2 W−1 and very low noise equivalent power of 8.94×10−14 W Hz−1/2 with 10.6 µm laser. The photo bolometer effect is responsible for the photoresponse in the infrared range with a large temperature coefficient resistance of −241.2% K−1. This study shows a new type of potential broadband response material and provides a promising LWIR optoelectrical device with good air stability.

Vortex dynamics has attracted tremendous attention for both fundamental physics and applications of type-II superconductors. However, methods to detect local vortex motion or vortex jump with high sensitivity are still scarce. Here, we fabricated soft point contacts on the clean layered superconductor 2H–NbSe2, which are demonstrated to contain multiple parallel micro-constrictions by scanning electronic microscopy. Andreev reflection spectroscopy was then studied in detail for the contacts. Differential conductance taken at fixed bias voltages was discovered to vary spontaneously over time in various magnetic fields perpendicular to the sample surface. The conductance variations become invisible when the field is zero or large enough, or parallel to the sample surface, which can be identified as the immediate consequence of vortex motion across a finite number of micro-constrictions. These results demonstrate point contact Andreev reflection spectroscopy to be a new potential way with a high time resolution to study the vortex dynamics in type-II superconductors.

Broadband photodetectors based on 2D layered materials provide great potential applications in night vision, sensing, and communications. However, it remains a challenge for detectors to achieve both high photoresponsivity and fast response. Here, a high‐sensitive photodetector based on ReS2/BP van der Waals (vdW) heterodiode with fast speed, rising time (τr) of 770 ns, and decay time (τd) of 760 ns under a 637 nm laser is reported. The detection range is covered from visible to mid‐wave infrared (MWIR) 0.405–3.753 μm. In the visible range, a high photoresponsivity of 107.1 AW−1, competitive specific detectivity (D*) of 1.89 × 1010 cm Hz1/2 W−1, and a low noise equivalent power of 3.03 × 10−14 W Hz−1/2 are obtained. In the MWIR the D* of 3.26 × 108 cm Hz1/2 W−1 is demonstrated in the photovoltaic model. Notably, the photodiode realizes a high external quantum efficiency of 71.8%, and a high power conversion efficiency of 2.0%. This work provides a way to design broadband response and fast‐speed self‐driven photodetectors with great potential applications in weak light intensity.