Charge Sensing and Controllable Tunnel Coupling in a Si/SiGe Double Quantum Dot

2009/05/11 by C. B. Simmons, Madhu Thalakulam, B. M. Rosemeyer +11 · 3 citations
Engineering · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Charge (physics) #Coupling (piping) #Gate voltage #Materials science #Optoelectronics #Physics #Quantum #Quantum and electron transport phenomena #Quantum dot #Quantum dot laser #Quantum mechanics #Quantum tunnelling #Qubit #Semiconductor #Semiconductor materials and devices #Silicon #Spin (aerodynamics) #Transistor #Voltage #cond-mat.mes-hall

paper · pdf · doi:10.1021/nl9014974

published as Nano Lett., 2009, 9 (9), pp 3234-3238 · 5 pages, 4 figures, submitted for publication

arxiv created 2009/05/11 · openalex publication_date 2009/07/31 · arxiv updated 2015/05/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We report integrated charge sensing measurements on a Si/SiGe double quantum dot. The quantum dot is shown to be tunable from a single, large dot to a well-isolated double dot. Charge sensing measurements enable the extraction of the tunnel coupling t between the quantum dots as a function of the voltage on the top gates defining the device. Control of the voltage on a single such gate tunes the barrier separating the two dots. The measured tunnel coupling is an exponential function of the gate voltage. The ability to control t is an important step toward controlling spin qubits in silicon quantum dots.

Citations

• Fabrication and characterization of electrostatic Si∕SiGe quantum dots with an integrated read-out channel
• A Ge/Si heterostructure nanowire-based double quantum dot with integrated charge sensor
• Coulomb blockade and Kondo effect in a few-electron silicon/silicon-germanium quantum dot
• Universal Quantum Computation with Spin-1/2Pairs and Heisenberg Exchange
• Magnetic field dependence of valley splitting in realistic Si∕SiGe quantum wells
• Exchange in Silicon-Based Quantum Computer Architecture
• Differential Charge Sensing and Charge Delocalization in a Tunable Double Quantum Dot
• Coherent Manipulation of Coupled Electron Spins in Semiconductor Quantum Dots
• Spin Echo of a Single Electron Spin in a Quantum Dot
• Single-shot read-out of an individual electron spin in a quantum dot

Cited by

• Tunable singlet-triplet splitting in a few-electron Si/SiGe quantum dot
• Palladium gates for reproducible quantum dots in silicon
• Single-Shot Measurement of Triplet-Singlet Relaxation in aSi/SiGeDouble Quantum Dot