Single-Electron Operation of a Silicon-CMOS 2 × 2 Quantum Dot Array with Integrated Charge Sensing

Area of Science:

• Quantum Computing
• Nanotechnology
• Semiconductor Physics

Background:

• CMOS technology offers advanced nanoscale integration for quantum computing.
• Early CMOS quantum dot devices show promise but lack individual electron control seen in university designs.

Purpose of the Study:

• To demonstrate remote charge sensing and control of quantum dots in CMOS nanowires.
• To enable the formation of a 2x2 array of quantum dots for quantum information processing.

Main Methods:

• Utilized a remote single electron transistor (SET) in an adjacent nanowire for measurement.
• Employed floating coupling gates to controllably form ancillary quantum dots.
• Applied effective mass theory to optimize geometrical parameters for interdot tunnel rates.

Main Results:

• Achieved charge sensing down to the last electron in each quantum dot.
• Demonstrated controllable formation of ancillary quantum dots under floating gates.
• Enabled precise control over a 2x2 array of quantum dots.

Conclusions:

• Remote SET measurement in CMOS nanowires provides advanced control over quantum dots.
• This approach is crucial for developing scalable spin-based quantum computing architectures.
• Optimizing device geometry is key to achieving necessary interdot tunnel rates for quantum computation.