What are spin qubits?

IBM has signed an agreement to acquire HRL Laboratories, a move focused on accelerating advancements in quantum computing. This acquisition brings HRL’s research in silicon-spin qubit engineering into the IBM portfolio, directly supporting the mission to scale quantum technology for practical, industrial use.

Spin qubits represent a specific approach to quantum information. Unlike superconducting qubits, spin qubits store information in the spin state of an electron—either up or down. HRL uses quantum dots created from silicon and germanium to confine and control these electrons. Their architecture, known as exchange-only qubits, uses three electrons per qubit to represent binary states, which allows for precise manipulation through electrical pulses.

The appeal of spin qubits lies in their manufacturing potential. Because they rely on existing semiconductor fabrication tools and processes, they offer a clear path toward large-scale production. They also operate at higher temperatures—approximately 1K—compared to the extremely low temperatures required for superconducting architectures. This physical advantage, combined with high coherence times and low error rates, makes them a practical choice for running large quantum circuits.

Beyond pure computation, the acquisition adds depth to the broader IBM quantum roadmap. HRL contributes expertise in quantum sensing and networking, which are critical for applications in navigation, defense, and healthcare. These technologies, alongside a portfolio of novel quantum materials, provide the tools to improve performance across the entire quantum stack.

HRL has already demonstrated a digitally controlled silicon-spin computer with 18 qubits, utilizing 54 quantum dots on three rails. By integrating this research and development team, IBM aims to broaden its technical capabilities. The focus remains on delivering reliable, scalable quantum systems that can address complex computational challenges.