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Layered metal monochalcogenides have attracted significant interest in the 2D family since they show different unique properties from their bulk counterparts. The comprehensive synthesis, characterization, and optoelectrical applications of 2D‐layered tin monosulfide (SnS) grown by pulsed laser deposition are reported. Few‐layer SnS‐based field‐effect transistors (FETs) and photodetectors are fabricated on Si/SiO2 substrates. The premium 2D SnS FETs yield an on/off ratio of 3.41 × 106, a subthreshold swing of 180 mV dec−1, and a field effect mobility (µFE) of 1.48 cm2 V−1 s−1 in a 14‐monolayer SnS device. The layered SnS photodetectors show a broad photoresponse from ultraviolet to near‐infrared (365–820 nm). In addition, the SnS phototransistors present an improved detectivity of 9.78 × 1010 cm2 Hz1/2 W−1 and rapid response constants of 60 ms for grow‐time constant τg and 10 ms for decay‐time constant τd under extremely weak 365 nm illumination. This study sheds light on layer‐dependent optoelectronic properties of 2D SnS that promise to be important in next‐generation 2D optoelectronic devices.

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A negatively biased collecting plate was used to collect the ion current of the cathodic arc plasma transported through a curved magnetic duct. The optimal duct bias at which the duct has the maximum efficiency for plasma transport was measured for C, Ti, Mo, and W plasmas as a function of the arc current and guiding magnetic field. The optimal bias decreased with the magnetic field and was almost steady when the field was above 400 G. The optimal bias at 400 G and above increased with the arc current for C plasma but the opposite relationship was observed for Ti, Mo, and W plasmas. The effects of the plasma density, ion mass, ion kinetic energy, and magnetic field on the optimal bias are discussed.