Charge states, triple points and quadruple points in an InAs nanowire triple quantum dot revealed by an integrated charge sensor

Abstract

A serial triple quantum dot (TQD) integrated with a quantum dot (QD) charge sensor is realized from an InAs nanowire via a fine finger-gate technique. The complex charge states and intriguing properties of the device are studied in the few-electron regime by direct transport measurements and by charge-sensor detection measurements. The measurements of the charge stability diagram for a capacitively coupled, parallel double-QD formed from a QD in the TQD and the sensor QD show a visible capacitance coupling between the TQD and the sensor QD, indicating a good sensitivity of the charge sensor. The charge stability diagrams of the TQD are measured by the charge sensor and the global features seen in the measured charge stability diagrams are well reproduced by the simultaneous measurements of the direct transport current through the TQD and by the simulation made based on an effective capacitance network model. The complex charge stability diagrams of the TQD are measured in detail with the integrated charge sensor in an energetically degenerate region, where all the three QDs are on or nearly on resonance, and the formations of quadruple points and of all possible eight charge states are observed. In addition, the operation of the TQD as a quantum cellular automata is demonstrated and discussed.

18 pages, 4 figures, Supplementary Information included

References in corpus (8)

• Semiconductor Spin Qubits
• Direct Measurement of the Spin-Orbit Interaction in a Two-Electron InAs Nanowire Quantum Dot
• An electrostatically defined serial triple quantum dot charged with few electrons
• Quantum simulation of Fermi-Hubbard models in semiconductor quantum dot arrays
• The 3D transport diagram of a triple quantum dot
• Coherent transport in a linear triple quantum dot made from a pure-phase InAs nanowire
• Measurements of the spin-orbit interaction and Landé g factor in a pure-phase InAs nanowire double quantum dot in the Pauli spin-blockade regime
• Detection of charge states of an InAs nanowire triple quantum dot with an integrated nanowire charge sensor

Cited by in corpus (1)

• Simulation of Charge Stability Diagrams for Automated Tuning Solutions (SimCATS)