A cryogenic amplifier for fast real-time detection of single-electron tunneling

Abstract

We employ a cryogenic High Electron Mobility Transistor (HEMT) amplifier to increase the bandwidth of a charge detection setup with a quantum point contact (QPC) charge sensor. The HEMT is operating at 1K and the circuit has a bandwidth of 1 MHz. The noise contribution of the HEMT at high frequencies is only a few times higher than that of the QPC shot noise. We use this setup to monitor single-electron tunneling to and from an adjacent quantum dot and we measure fluctuations in the dot occupation as short as 400 nanoseconds, 20 times faster than in previous work.

4 pages, 3 figures

References in corpus (4)

• Single-shot read-out of an individual electron spin in a quantum dot
• Single-shot readout of electron spin states in a quantum dot using spin-dependent tunnel rates
• Using a quantum dot as a high-frequency shot noise detector
• Excited-state spectroscopy on a nearly-closed quantum dot via charge detection

Cited by in corpus (6)

• Time-resolved charge detection in graphene quantum dots
• Measuring current by counting electrons in a nanowire quantum dot
• An in-situ tunable radio-frequency quantum point contact
• Radio-frequency reflectometry on large gated 2-dimensional systems
• Radio frequency pulsed-gate charge spectroscopy on coupled quantum dots
• Josephson squelch filter for quantum nanocircuits