Liquid metal alloy ion sources for quantum applications

Most approaches to implant single or few ions for quantum applications require the use of focused ion beams (FIB). In addition to the detection of ion implantation and laterally precise placement, the first consideration should also be the species as well as the emittance of the ion beam itself. While elements that are gaseous at room temperature can mainly provided by Gas Field Ion Sources or Plasma Ion Sources, most of the metals and semimetals afford the utilization of Liquid Metal Ion Sources (LMIS).

Gallium has established in industry and science as easiest and most stable type of LMIS. For quantum applications other ion species like Li, B, C, N, Al, Si, P, Sb, Bi or the rare earth elements became from higher interest [1-6]. We give an overview about published metal alloys for FIBs and give an insight into the development and production of new sources. Finally, we give an outlook on current and future applications and activities.

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