Towards imaging of single impurities in silicon
Murdin
Abstract:
Shallow donor impurities in silicon are ubiquitous in room-temperature microelectronics, but once frozen at low temperature, they share many properties in common with free hydrogen atoms. These donors sit in the cleanest possible crystalline environment, almost like being trapped in vacuum, and this means that quantum properties of superpositions and entanglement become very long lived. Although they have held the record for the longest electronic spin relaxation lifetimes in the solid state for over half a century, it has only very recently been possible to investigate the orbital motion and relaxation. The reason for the difficulty is the lack of short, intense pulses in the relevant wavelength range, around 10THz. The most flexible source for study is the Free Electron Laser, such as FELIX in Nijmegen, but we are developing new table-top THz sources.
In this talk I will describe how silicon donors may be used for quantum information processing, how we are working towards imaging and control of individual donor atom, and what optical and microwave microscopy technologies we are developing in conjunction with the new sources.