Quantum Point Contact as Charge Detector

This lecture discusses the use of a quantum point contact (QPC) as a charge detector in quantum systems, focusing on real-time charge detection and its applications in quantum dots. It covers the principles behind QPC operation, conductance measurements, and the detection of charge transitions between quantum dots. The lecture also explores the impact of gate voltages on QPC behavior, the influence of inter-dot capacitance and cross-talk in coupled quantum dots, and the methods for initializing and reading out single electron spins. Various experimental techniques and theoretical concepts related to charge qubits, spin qubits, singlet-triplet qubits, and exchange qubits are presented.