From Electron Pumps to Spin Quantum Bits in Silicon

Motivated by electrical quantum metrology of the ampere we have developed versatile silicon CMOS based single-electron transistors and quantum dots. Besides charge quantization we can also control the spin degree of freedom of a single holes or electrons confined in those dots. Spin resonance has been observed in both cases although it was less expected for electrons. Furthermore we demonstrated the first spin hole quantum bit in CMOS technology, which offers exciting prospects most notably for scaling as its control is purely electrical thanks to spin-orbit interaction.