The 2025 Nobel Prize in Physics: How Superconducting Circuits Became Quantum Computers

The 2025 Nobel Prize in Physics went to John Clarke, Michel Devoret, and John Martinis for experiments that proved something extraordinary: quantum mechanics doesn't just govern tiny particles. With the right engineering, you can make macroscopic electrical circuits behave quantum mechanically, too.

This wasn't just a physics curiosity; it became the foundation for every superconducting quantum computer being built today.

Why This Nobel Matters for Quantum Computing

Before Clarke, Devoret, and Martinis, quantum effects were confined to the microscopic world, single atoms, photons, and electrons under ultra-controlled conditions.

The open question was: how big can a quantum system be? Can we actually build something useful with it?

Their answer came through experiments with superconducting circuits using Josephson junctions, special components that allow electrical currents to exhibit quantum tunneling and energy quantization. 

Schrödinger's Cat, Scaled Up

Theorist Anthony Leggett compared the laureates' macroscopic quantum system to Erwin Schrödinger's famous thought experiment featuring a cat in a box, simultaneously alive and dead until observed. Schrödinger's 1935 thought experiment was intended to show the absurdity of quantum superposition at macroscopic scales; after all, you can't actually put a cat into quantum superposition in a lab.

However, Leggett argues that the experiments by Clarke, Devoret, and Martinis demonstrated phenomena involving vast numbers of particles that together behave exactly as quantum mechanics predicts. While their macroscopic system of Cooper pairs is still many orders of magnitude smaller than a kitten, it measures quantum mechanical properties that apply to the system as a whole. For a quantum physicist, it's remarkably similar to Schrödinger's imaginary cat.

This type of macroscopic quantum state offers new potential for experiments using phenomena that govern the microscopic world. It functions as a form of artificial atom on a large scale—an atom with cables and sockets that can be connected into new experimental setups or utilized in quantum technology. These artificial atoms are now used to simulate other quantum systems and aid in understanding them.

That insight underpins nearly every superconducting qubit in development today.

Three Pioneers, Three Eras of Progress

1970s-1980s: Proving Macroscopic Quantum Behavior

John Clarke was among the first to demonstrate that macroscopic circuits could follow quantum mechanical rules. His work with Josephson junctions and SQUIDs (Superconducting Quantum Interference Devices) provided experimental proof that quantum tunneling and superposition could exist in electrical circuits. Before Clarke, the notion that a circuit could be a qubit would have seemed absurd. He proved it was possible.

1980s-2000s: Engineering Quantum Circuits

Working at CEA Saclay in France, Michel Devoret and his collaborators built the theoretical and experimental framework for controlling these macroscopic quantum effects. They designed circuits like the Cooper pair box that could hold and manipulate quantum information, essentially creating the discipline of "quantum electrical engineering." Devoret also trained a generation of quantum engineers, including John Martinis, who transformed these principles into practical systems.

1990s-present: Building the Quantum Processor

John Martinis took those principles and built the first high-coherence superconducting qubits. He refined the transmon qubit architecture (with Yale's Robert Schoelkopf and Steven Girvin) and led the Google Quantum AI team that achieved quantum supremacy in 2019, where their Sycamore processor outperformed classical supercomputers on a specific task. Martinis showed these circuits could scale into programmable quantum processors. The transmon-based approach is now used by Google, IBM, Rigetti, and others.

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The Google Connection

This Nobel story is deeply connected to Google's quantum roadmap. Michel Devoret currently serves as Chief Scientist of Quantum Hardware at Google. John Martinis led Google's quantum hardware team from 2014 until recently, bringing his UC Santa Barbara team to Google specifically to build superconducting quantum processors.

Google's quantum computing platform is built directly on the foundation these Nobel laureates created.

Google's Next Move: The Atlantic Quantum Acquisition

In a development announced just last week, Google acquired Atlantic Quantum—a move that signals where superconducting quantum computing is heading next.

Atlantic Quantum's key innovation is fluxonium qubits, a newer superconducting qubit design that addresses some fundamental limitations of the widely used transmon. Fluxonium offers dramatically longer coherence times, lower error rates, and improved scalability—all critical for efficient error correction and large-scale, fault-tolerant quantum processors.

The acquisition also brings Google direct access to MIT's leading superconducting qubit research community, along with proprietary designs that move beyond transmon's inherent limits. Atlantic Quantum's modular chip stack integrates qubits with superconducting control electronics within the cold stage itself, reducing complexity, noise, and wiring overhead by embedding control closer to the qubit environment.

This could be a strong indication that Google is preparing to evolve beyond transmons into next-generation architectures.

What This Means for the Quantum Ecosystem

It Validates Quantum Hardware as Real Engineering, Not Just Physics

Clarke, Devoret, and Martinis didn't just theorize quantum coherence; they tamed it. They built the control electronics, noise shielding, and measurement chains that turned a single qubit in a fridge into a programmable, scalable platform. That recognition gives deep legitimacy to companies working on hardware scalability, error correction, and system integration.

It Strengthens Industry Credibility for Investors and Governments

For investors, this is a narrative unlock. It signals that:

• The core physics is mature

• The field has entered the engineering and scaling era

• The Nobel Foundation, the ultimate arbiter of foundational science, confirms that quantum computing is not speculative but real science with measurable results

This is expected to fuel new investment rounds, government grant programs, and corporate partnerships across Europe, the U.S., and Asia.

It Sets the Stage for the Next Wave of Innovation

Every Nobel tends to crystallize a past paradigm and provoke the next. This one honors superconducting qubits, but it also sets a benchmark for innovation, as we see with fluxonium and Atlantic Quantum, as well as emerging modalities like spin qubits, neutral atoms, and photonics.

For companies in the quantum stack, especially those working on cryogenic control, qubit interconnects, and error correction, this represents a clear opportunity. As industry leaders like Google move toward more sophisticated qubit designs with tighter cold-integration requirements, the demand for enabling technologies will accelerate.

The Bottom Line

The 2025 Nobel Prize in Physics validates decades of effort by scientists who turned quantum mechanics from mystery into machinery. It also signals that quantum tech is moving from labs to markets, becoming central to how we'll compute, communicate, and create materials in the coming decades.

Expect a surge in momentum: more venture capital for quantum startups, new partnerships between big tech and academia, and government programs expanding national quantum strategies. The global race is no longer about "quantum supremacy"; it's about quantum usefulness: applying quantum systems to solve real problems.

For companies, this means opportunity. Whether through hardware, software, or quantum-inspired algorithms, those integrating quantum thinking into their products and strategy stand to lead the next wave of innovation.