Manufacturing qubits that can move

In the quest to unlock the potential of quantum computing, the demand for high-quality qubits is paramount. These qubits need to be organized into groups that can function as error-corrected logical qubits. Various companies are exploring unique pathways to achieve this goal, generally falling into two main categories. On one side, some organizations focus on embedding qubits within electronic components that can be mass-produced, ensuring a steady supply of devices. Conversely, other companies utilize atoms or photons as qubits, offering more reliable performance but requiring complex hardware for management. A significant advantage of systems leveraging atoms or ions is their mobility, which facilitates the entanglement of any qubit with another. This flexibility is crucial for effective error correction. In contrast, electronic device-based systems are somewhat restricted by their manufacturing configurations. Recent research has shed light on a promising approach that combines the strengths of both methodologies. This study investigates quantum dots, which can be produced in large quantities and house a qubit represented by a single electron's spin. Remarkably, the findings indicate that these spin qubits can be relocated between quantum dots without compromising quantum information. The ability to move qubits opens up possibilities for the versatile connectivity akin to that of atoms and ions. Quantum dots effectively manage an electron’s behavior by confining it in a space smaller than its wavelength. Their compact design allows for the integration of numerous quantum dots into chip manufacturing processes. This advancement enables the creation of chips populated with multiple quantum dots, as well as the necessary gates and devices for controlling their function. To utilize these as qubits, electronic systems are employed to introduce a single excess electron into a quantum dot. Given that electrons possess a characteristic known as spin, their states can be manipulated to exist in either spin-up or spin-down configurations, or in a superposition of both. While electron-based qubits are generally sensitive to environmental disturbances, quantum dots offer a degree of isolation that enhances their stability and performance, making them a promising avenue for the future of quantum computing.