Temperature dependence of photo-hole decay in 4d derived Quantum Well States in monolayer Ag(111) films on Pd(111), Ni(111), Mo(110) and Cu(100)

We present experimental data on the temperature dependence of photo-hole decay obtained by Angle Resolved Photoemission (ARPES) measurements from 4d derived Quantum Well States (QWS) on Ag(111) monolayer films deposited on Pd(111), Ni(111), Mo(110) and Cu(100). We have found a significant increase of the Ag 4d electron-phonon (e-ph) coupling strength with respect to the bulk values. The increase is attributed to different mechanisms that are associated with the interaction of the Ag film with under laying substrate. It is proposed that the main channels that contribute to the increased e-ph coupling originate from the inter-band transitions that involve bulk states of the substrates.

► The electron-phonon coupling measured in the 4d QW state doublet in Ag(111) monolayers. ► The ratio of coupling constants of the QWS doublet varies in the range of 1.8 to 4.0. ► The values are different on different substrates, increased with respect to the bulk. ► We conclude that they can be substantially affected by the interaction with substrate. ► These experimental results might stimulate future theoretical modelling.