Scientists have demonstrated the use of a robotic arm in quantum technology. The arm, equipped with a magnet, can sensitise a quantum magnetometer in challenging conditions. This development could increase speed, control, and robustness in quantum technology applications. The team’s work suggests that robotics could replace traditional methods in experimental physics and quantum technologies, particularly in highly constrained environments. The next step is to develop an algorithm that can generate on-demand magnetic fields, potentially revolutionising the field of quantum technology.
Quantum Technology and Robotics Integration
The development of practical quantum technologies requires the precise manipulation of fragile systems in a robust and repeatable manner. As quantum technologies advance towards real-world applications, such as biological sensing and space communication, the increasing complexity of experiments introduces constraints that can be alleviated by the introduction of new technologies. Robotics, with its significant progress in creating smart, autonomous, and highly dexterous machines, offers a promising solution. Reported in Advanced Science, the team from Bristol UK published their work in November 2023.
The Role of Robotics in Quantum Technology
Experiments designed to exploit quantum technologies for applications can be extremely challenging. Fragile quantum states must be delicately manipulated, while minimising sources of decoherence, in order to preserve a quantum advantage. This often necessitates cutting-edge experimental physics, including precise and complex optical assemblies, strong vector magnetic fields, high-speed microwave delivery, and compatibility with extremely low-temperature environments.
As these proof-of-principle devices become more sophisticated and start to scale in size and complexity, established lab infrastructure such as translation stages and solenoid coils will no longer provide the flexibility, speed, and precision to meet these constrained and sometimes competing experimental requirements. In contrast, the field of robotics has long adapted to operate robots in challenging conditions, such as at the microscale or in very low-temperature environments. Robotics can provide more flexible and adaptable approaches than traditional methods, which would speed up the deployment of quantum technology across applications.
Robot-Assisted Quantum Technology
The study introduced and validated the idea of robot-assisted quantum technology. Specifically, a robotic arm was used to hold a strong permanent magnet to meet a requirement in spin-based sensing: aligning an external magnetic field along the magnetic dipole axis of an arbitrarily oriented spin system. This method has significant advantages where traditional techniques for generating vector fields, such as mounting the magnet on a fixed axis translation stage, or using a three-axis Helmholtz coil, are infeasible owing to the tight physical constraints of the surrounding optomechanical apparatus.
Advantages of Robotics in Quantum Technology
The results showed that an industrially designed robotic arm can be adapted to operate around sensitive optomechanical samples and setups. The robotic arm produces stable and controllable magnetic fields that are capable of manipulating and aligning a single solid-state quantum spin sensor. This is an important step in the use of robotics to replace axial stages and bulky field coils for experimental physics and in developing quantum technologies, where the benefit of the innate flexibility and configurability of robotic arms in highly constrained environments has been evidenced.
Future Prospects of Robotics in Quantum Technology
The next step in this work is to generate on-demand magnetic fields using a sophisticated algorithm that maps the traversable space given geometrical parameters, making use of the collision-free techniques described. With this, a set of control points can be found, considering application-specific criteria such as the field magnitude, linearisation, or the time taken to move between points.
Robotics, unlike solenoid coils, produce minimal local heat. This makes them suited for sensitive samples, and algorithms could be designed for tracking quantum sensors in motion under cell uptake, a difficult task where the spin sensor orientation changes over time. For further flexibility, the cylindrical magnet could be replaced with a rectangular magnet fixed perpendicular to its magnetic axis, with the unused roll degree of freedom in the robotic wrist providing rapid field orientation.
Beyond an off-the-shelf design, an application-specific robot could further maximise efficiency, precision, and control. This could have a larger payload whilst having a smaller form factor, for instance. We can extend this to the use of multiple robots to generate gradient magnetic fields. Without our approach, we find a 99% field uniformity over millimetre volumes. However, this is significantly less than Helmholtz coils, which maintain this uniformity over their central volume (> cm3). To combat this, multiple robots could be combined to increase uniformity over large areas. As well as a range of solid-state sensors, the alignment of atoms and ions in cold and vacuum environments can be explored with these form factors. A probe-like flux concentrator appended to the end-effector could achieve higher field strengths at distant locations, although the presence of this ferromagnet would have to be robustly modelled.
In addition, the robot-driven orientation presented can be extended to aligning quantum objects with a range of parameters, including electric and light fields. Here, the end effector would be an electrode, or in optics, a laser or mirror surface. Following this proof-of-principle work, the adaptability of robots in combination with sophisticated software could provide ruggedness for alignment in demanding real-world environments where quantum technologies are emerging, such as point to point quantum key distribution (QKD) and quantum range finding.
“Researchers have successfully used a robotic arm to manipulate a quantum sensor, a significant step towards practical quantum technologies. This development could increase the speed, control, and robustness of quantum technology applications, particularly in challenging conditions where traditional techniques are inadequate.”
- Researchers Joe A. Smith, Dandan Zhang, and Krishna C. Balram have developed a method to improve the manipulation of quantum systems using robotics.
- The team used a robotic arm equipped with a magnet to sensitise a Nitrogen-Vacancy (NV) centre quantum magnetometer, a device used for precise magnetic field detection.
- The robotic arm was able to generate vector magnetic fields with high accuracy, determining the orientation of a single spin-based sensor in a constrained physical environment.
- This method has significant advantages over traditional techniques for generating vector fields, such as mounting the magnet on a fixed axis translation stage, or using a three-axis Helmholtz coil.
- The use of robotics in this context could increase prototyping speed, control, and robustness in quantum technology applications.
- The researchers also suggest that robotics could be used to generate on-demand magnetic fields using a sophisticated algorithm, and could be adapted for tracking quantum sensors in motion.
- This work could have implications for a range of quantum technologies, including quantum key distribution and quantum range finding.