10 Quantum hardware
Koen Groenland · Amsterdam University Press eBooks · 2025
Quantum hardwareConventional computer hardware is extremely reliable.Professional servers are supposed to run non-stop for years without any hardware failures.If you take a new product out of a box, you can be reasonably sure that it will work precisely as advertised -and if does not, it should be straightforward to replace.Moreover, classical IT is extremely well-standardised.No matter what supplier you buy a computer from, you can be reasonably sure you can run your favourite applications on them.Thanks to such high reliability and clear compatibility, it is rather easy to compare different machines, for example, by looking at speed (e.g.floating-point operations per second, FLOPS) and memory size.We will see that this is radically different for quantum computers.Devices make mistakes, have limited functionalities, and memory is scarce compared to classical computing standards.Several manufacturers focus on niche applications, making trade-offs in certain features to enhance performance in others.In this chapter, we take a high-level perspective at quantum computing hardware.We address the two most important aspects: -What functionality does a device have?-What type of qubits are used?