Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor

Details Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor

2009-10-19

arxiv.org/abs/0910.3631v1

Appl. Phys. Lett. Vol. 96, 042101 (2010)

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

3 pages, 3 figures

Scientific paper

10.1063/1.3280368

We report on the fabrication and characterization of a few-electron quantum dot controlled by a single gate electrode. Our device has a double-quantum-well design, in which the doping controls the occupancy of the lower well while the upper well remains empty under the free surface. A small air-bridged gate contacts the surface, and is positively biased to draw laterally confined electrons into the upper well. Electrons tunneling between this accumulation-mode dot and the lower well are detected using a quantum point contact (QPC), located slightly offset from the dot gate. The charge state of the dot is measured by monitoring the differential transconductance of the QPC near pinch-off. Addition spectra starting with N=0 were observed as a function of gate voltage. DC sensitivity to single electrons was determined to be as high as 8.6%, resulting in a signal-to-noise ratio of ~9:1 with an equivalent noise bandwidth of 12.1 kHz. Analysis of random telegraph signals associated with the zero to one electron transition allowed a measurement of the lifetimes for the filled and empty states of the one-electron dot: 0.38 ms and 0.22 ms, respectively, for a device with a 10 nm AlInAs tunnel barrier between the two wells.

Affiliated with

Also associated with

No associations

Rating

Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Single-Gate Accumulation-Mode InGaAs Quantum Dot with a Vertically Integrated Charge Sensor will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-716540