Thermal-error regime in high-accuracy gigahertz single-electron pumping

Speaker: 
Mr Ruichen Zhao
From: 
UNSW CQC2T
When: 
4pm Thursday 16 March 2017
Where: 
CQC2T Conference Room, Level 2 Newton Building, UNSW

Single-electron pumps based on semiconductor quantum dots are promising candidates for the emerging quantum standard of electrical current. They can transfer discrete charges with part-per-million (ppm) precision in nanosecond time scales. Here, we employ a metal-oxide-semiconductor silicon quantum dot to experimentally demonstrate high-accuracy gigahertz single-electron pumping in the regime where the thermal excitation of electrons, during the equilibrium charge capturing process, is the predominant error mechanism. Despite severe drive-induced heating in one of the electron reservoirs, the large addition energy of the quantum dot efficiently suppresses the thermal errors to an extremely low level. In a measurement with traceability to primary voltage and resistance standards, the averaged pump current over the quantized plateau, driven by a 1GHz sinusoidal wave in the absence of magnetic field, is equal to the ideal value of ef within a measurement uncertainty as low as 0.27ppm.