Single Top Physics at ATLAS and CMS

The measurement of single-top production opens up a wide field for tests of the Standard Model (SM) and searches for phenomena beyond as e.g. Flavour Changing Neutral Currents, anomalous couplings, top-quark polarisation or monotop production. In contrast to the top-pair production, top quarks are produced in electro-weak interactions and provides insights into the properties of the $Wtb$ vertex. Making use of a luminosity of 20.3 fb$^{-1}$ at $\sqrt{s}$ = 8 TeV and of 3.3 fb$^{-1}$ at $\sqrt{s}$ = 13 TeV the ATLAS and CMS experiments provided measurements for all single top channels predicted by the SM. The well established observation of the $t$-channel allowed for precise measurements as differential of fiducial cross sections. The production cross section of a single top quark in association with a $W$-boson could be measured at good precision. For the first time, also the $s$-channel production cross section could be measured making use the new, sophisticated matrix element method. Based on the precise SM measurements, the properties of the $V_{tb}$ matrix element and the top quark polarisation could be measured. This lays the basis for the searches for physics beyond the SM (BSM), So far, no deviation from the SM predictions could be observed in single top analyses.