This Special Issue is devoted to electrons and ions in and on liquid helium, and related systems. It contains contributions presented at the International Workshop “Electrons and Ions in/on Helium (EIH-2020)”, which was organized by the Centre for Nano Science and Engineering (CeNSE), Indian Institute of Science (IISc) Bangalore on 23–25 January, 2020. This workshop is part of a series of similar meetings on this topic, starting 2006 in Paris, and since then taking place about every two years; the previous one was held in Mishima (Japan). Over 50 researchers from all over the world participated in the EIH-2020 workshop, with talks covering a range of topics from two-dimensional systems of electrons above liquid helium, multi- and single-electron bubbles in superfluid helium, to single electron-based qubits as well as interactions of electrons and neutral particles with quantized vortices.
At the beginning of the meeting pre-conference tutorials were given, chaired by Prof. Akshay Naik, IISc Bangalore. The topics in the pre-conference tutorial included electrons above helium, electron bubbles and quantum computing based on electrons above helium. Subsequently, there were research talks from multiple speakers spread over the next three days. In addition, there was a poster session in which the following participants were awarded for best posters: Hala Siddiq (UK), Surajit Dutta (India), Che-Chi Shih (Taiwan), Pranaya Kishore Rath (India). The three-day workshop was sponsored by SPARC (MHRD, Govt. Of India), Institute of eminence (IOE) program at IISc, Oxford instruments, and Zurich instruments. The event concluded with a trip to Nrithyagram, a residential school for Indian classical dances, and a banquet dinner.
I would like to thank all collaborators who helped to make this workshop a success, in particular Grace, Akila, Neha, Dillip, Zhuolin, Yunhu, Pranaya and Neda.
(Conference Chairman and Guest Editor).
Participants at the International Workshop “Electrons and Ions in/on Helium (EIH-2020)”, Centre for Nano Science and Engineering (CeNSE), Indian Institute of Science (IISc), Bangalore, India, on 23rd–25th January, 2020".