The paper presents a method for single-shot read-out of an individual electron spin in a semiconductor quantum dot. The authors use spin-to-charge conversion, where the spin state of a single electron confined in the quantum dot is correlated with its charge state, and detect the charge using a quantum point contact (QPC). The spin measurement visibility is approximately 65%. They also observe long single-spin energy relaxation times, up to about 0.85 ms at a magnetic field of 8 Tesla, which is promising for using electron spins as quantum information carriers. The experimental setup involves a quantum dot in close proximity to a QPC, with the quantum dot used to trap a single electron and the QPC to detect its presence. The device is placed in a dilution refrigerator and subjected to a magnetic field. The Zeeman splitting in the dot is larger than the thermal energy but smaller than the orbital and charging energies. The authors use a two-level pulse technique to inject and measure the spin state of a single electron, demonstrating the validity of their method through detailed analysis of the QPC response. They also measure the single-spin energy relaxation time, \( T_1 \), which is found to be around 0.55 ms at 10 Tesla, significantly longer than previously reported values. The measurement fidelity, which characterizes the accuracy of the single-shot spin read-out, is determined to be around 0.93 for spin-up and 0.72 for spin-down states. These results are encouraging for the use of electron spins in quantum information processing.The paper presents a method for single-shot read-out of an individual electron spin in a semiconductor quantum dot. The authors use spin-to-charge conversion, where the spin state of a single electron confined in the quantum dot is correlated with its charge state, and detect the charge using a quantum point contact (QPC). The spin measurement visibility is approximately 65%. They also observe long single-spin energy relaxation times, up to about 0.85 ms at a magnetic field of 8 Tesla, which is promising for using electron spins as quantum information carriers. The experimental setup involves a quantum dot in close proximity to a QPC, with the quantum dot used to trap a single electron and the QPC to detect its presence. The device is placed in a dilution refrigerator and subjected to a magnetic field. The Zeeman splitting in the dot is larger than the thermal energy but smaller than the orbital and charging energies. The authors use a two-level pulse technique to inject and measure the spin state of a single electron, demonstrating the validity of their method through detailed analysis of the QPC response. They also measure the single-spin energy relaxation time, \( T_1 \), which is found to be around 0.55 ms at 10 Tesla, significantly longer than previously reported values. The measurement fidelity, which characterizes the accuracy of the single-shot spin read-out, is determined to be around 0.93 for spin-up and 0.72 for spin-down states. These results are encouraging for the use of electron spins in quantum information processing.