The electrical manipulation of magnetization and exchange bias in antiferromagnet/ferromagnet thin films could be of use in the development of the next generation of spintronic devices. Currentcontrolled magnetization switching can be driven by spin-orbit torques generated in an adjacent heavy metal layer, but these structures are difficult to integrate with exchange bias switching and tunnelling magnetoresistance measurements. Here, we report the current-induced switching of exchange bias field in a perpendicularly magnetized IrMn/CoFeB bilayer structure using a spinorbit torque generated in the antiferromagnet IrMn layer. By manipulating the current direction and amplitude, independent and repeatable switching of the magnetization and exchange bias field below the blocking temperature can be achieved. The critical current density for the exchange bias switching is found to be larger than that for CoFeB magnetization reversal. X-ray magnetic circular dichroism, polarized neutron reflectometry measurements and micromagnetic simulations show that a small net magnetization within the IrMn interface plays a crucial role in these phenomena.2 Electrical manipulation of the magnetization and exchange bias in antiferromagnet (AFM)/ferromagnet (FM) heterostructures 1-10 is expected to be of use in several high-performance spintronic devices, including magnetic tunnel junctions and magnetoresistance sensors. An efficient method for electrical switching of the FM magnetization is to use the spin-orbit torque (SOT) generated from a heavy metal (such as W, Ta, Pt) layer in AFM/FM/heavy metal structures 4,5,[11][12][13][14] .The in-plane exchange field generated at the AFM/FM interface enables field-free switching of the perpendicular magnetization and, compared to spin-transfer torque (STT)-driven devices, SOTdriven systems can potentially offer decreased switching times and thus faster data writing 15 .However, manipulation of the exchange bias is usually achieved by field cooling, which requires an external magnetic field and high temperature, hindering its application in practical devices 1,16,17 .Alternatively, it has recently been demonstrated that the exchange bias field at the AFM/FM interface can be switched by the SOT generated in the Pt layer in a Pt/Co/IrMn structure, passing through the thin Co layer 6 . Strong SOTs can also be generated in certain AFM thin films (such as IrMn and PtMn) due to their giant spin Hall angle [18][19][20][21][22] , allowing simpler spintronic devices to be created [23][24][25] . For example, field-free switching of perpendicular magnetization has been achieved in PtMn/[Co/Ni]n structures where no heavy metal layer is required, with both the in-plane exchange bias and SOT originating from the AFM/FM system 23 . An advantage of using an AFM/FM/oxide stack is that it is easier, compared to AFM/FM/heavy metal structures, to integrate tunnelling magnetoresistance (for electrical reading of FM magnetization 26,27 ), SOT and exchange bias switching in a single device.In this Article, we repo...

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Chemical reactions conducted in different media (liquid phase, gas phase, or surface) drive developments of versatile techniques for the detection of intermediates and prediction of reasonable reaction pathways. Without sample pretreatment, ambient mass spectrometry (AMS) has been applied to obtain structural information of reactive molecules that differ in polarity and molecular weight. Commercial ion sources (e.g., electrospray ionization, atmospheric pressure chemical ionization, and direct analysis in real-time) have been reported to monitor substrates and products by offline reaction examination. While the interception or characterization of reactive intermediates with short lifetime are still limited by the offline modes. Notably, online ionization technologies, with high tolerance to salt, buffer, and pH, can achieve direct sampling and ionization of ongoing reactions conducted in different media (e.g., liquid phase, gas phase, or surface). Therefore, short-lived intermediates could be captured at unprecedented timescales, and the reaction dynamics could be studied for mechanism examinations without sample pretreatments. In this review, via various AMS methods, chemical reaction monitoring and mechanism elucidation for different classifications of reactions have been reviewed. The developments and advances of common ionization methods for offline reaction monitoring will also be highlighted.