|The world of atoms is governed by the rules of quantum mechanics. Over the past century, quantum-mechanical phenomena such as superposition and entanglement have been observed and studied with great precision. Today, we are entering a new era in which we can hope to explore quantum mechanics in larger objects. The science of quantum mechanics in more complex objects is barely known and as a result quantum mechanics is rarely explicitly used in technology. Theoretically, superposition and entanglement could be exploited as a new resource in a wide variety of future applications. We focus on information science and investigate the use of quantum mechanics in computing, i.e. a quantum computer (QC). If information is encoded in quantum superpositions and processed by exploiting entanglement, a QC can solve computational problems that are beyond the reach of conventional computers. Building a QC is, however, an enormous scientific challenge because the fragile quantum bits need to be protected from and corrected for even the smallest disturbances by the environment. Meeting this challenge requires a synergetic effort combining the best of quantum theory, electrical engineering, materials science, applied physics and computer science. This proposal aims to achieve a robust, exemplary QC. We propose a circuit containing processor qubits (two types: superconducting transmon qubits and spin qubits in silicon quantum dots), memory qubits (two types: topological qubits with nanowires and donor qubits), and a quantum databus (superconducting striplines). Our goal is to demonstrate a 13-qubit circuit that incorporates fault-tolerance through implementation of a surface code. We will demonstrate back-and-forth quantum state transfer between processor and memory qubits. Our team brings together the required expertise into a single “QC-lab” enabling us to bring our understanding of quantum mechanics to the next level and push QC to the tipping point from science to engineering.