⚛️ From Atoms to Circuits — The Physics Behind the 2025 Nobel Prize

A Newsletter for Entrepreneurs, Investors, and Computing Geeks

Author

Emily Eisenblätter
October 13, 2025

Happy Monday! Here’s what’s inside this week’s newsletter:

  • Deep dive: The physics behind the 2025 Nobel Prize and how the laureates showed that quantum effects can appear in classical systems, demonstrating tunnelling and quantised energy in a hand-sized circuit, laying the groundwork for today’s superconducting qubits and quantum sensors.

  • Spotlights: NTT’s creation of the world’s first programmable nonlinear photonics chip, a breakthrough that kills the “one device, one function” rule, and Cerebras clarifying its IPO withdrawal after it’s $1.1B round.

  • Headlines: Semiconductor updates from Intel’s new processor architecture to EU policy moves, breakthroughs in continuous-operation quantum computing, and progress across photonics, neuromorphic systems, data centers, and cloud.

  • Readings: AI-driven semiconductor trends, quantum use cases for memristors, programmable photonic architectures, neuromorphic applications in sensing, and the next wave of connectivity with 5G-A and 6G.

  • Funding news: Last week’s funding centered on early-stage rounds in AI, cloud, semiconductors, and quantum, with Reflection AI’s $2B Series B highlighting the widening gap between infrastructure plays and platforms.

  • Bonus: The AI chip race turned circular: OpenAI is buying billions in AMD GPUs using AMD’s own stock while continuing major deals with Nvidia. The moves give OpenAI stakes and supply from both chipmakers.

Deep Dive: From Atoms to Circuits — The Physics Behind the 2025 Nobel Prize

The Nobel Discovery

Last week, the 2025 Nobel Prize in Physics was awarded to John Clarke, Michel Devoret, and John Martinis “for the discovery of macroscopic quantum mechanical tunnelling and energy quantisation in an electric circuit.”

The laureates proved that even in the world of classical physics, quantum effects can be observed. Their experiments demonstrated both 1) quantum tunnelling and 2) quantised energy levels in a system large enough to be held in the hand.

The Experiment That Proved It

The breakthrough was achieved in 1984–1985 at the University of California, Berkeley, where the team built an electrical circuit made of two superconductors separated by a thin insulating barrier, known as a Josephson junction.

When cooled to near absolute zero, electrons in the superconductors form Cooper pairs that move collectively as a single quantum system. The researchers observed that this system could tunnel through an energy barrier, switching from a zero-voltage state to one with a measurable voltage, providing direct evidence of macroscopic quantum tunnelling.

By introducing microwaves at controlled frequencies, the researchers further demonstrated that the system exhibited quantised energy levels, absorbing and emitting energy only in discrete amounts as predicted by quantum theory.

How Their Discovery Shapes Today’s World

The Josephson junctions used in the Nobel-winning experiments became the basis of superconducting qubit quantum computers. In these systems, quantum information is encoded in the discrete energy states of superconducting circuits. Such circuits (often described as artificial atoms) absorb and emit energy in quantised amounts, exactly as predicted by quantum theory.

In addition, the discovery laid the groundwork for technologies such as quantum sensors capable of detecting extremely small magnetic fields, ultra-precise measurement tools, and secure quantum communication methods.

The Concepts Explained

Quantum tunnelling: A quantum effect in which a particle crosses an energy barrier that it cannot overcome according to classical physics. It occurs because particles have wave-like properties, allowing their probability waves to extend into and beyond regions that would normally be inaccessible. This makes it possible for them to appear on the other side of the barrier and underlies processes such as radioactive decay and nuclear fusion.

Quantised energy levels: The principle that a quantum system can occupy only specific, discrete energy states rather than a continuous range, absorbing or emitting energy only in fixed amounts. This principle explains phenomena such as atomic spectra and the operation of lasers.

For those that want to explore the underlying physics in more detail, the “Scientific Background” paper offers an excellent deep dive into the experiments and theory.

Sources: Scientific Background; Popular Science Background; Press Release (Royal Swedish Academy of Sciences - Nobel Prize, 2025)

Spotlights

“NTT Research announced that it […] has created the world’s first programmable nonlinear photonic waveguide. The device can be reconfigured in real-time to perform any of several nonlinear-optical functions, such as second-harmonic generation, arbitrary pulse shaping, or holographic light synthesis, by projecting a structured light pattern onto a silicon-nitride core. The breakthrough […] promises to break the long‑standing “one device, one function” rule that has constrained photonic engineering for decades.
[…]
‘These results mark a departure from the conventional paradigm of nonlinear optics, where device functions are permanently fixed during fabrications,’ said Ryotatsu Yanagimoto, a scientist at NTT Research. , Ryotatsu Yanagimoto, NTT Research.
[…]
NTT’s announcement comes at a time when the photonic‑integrated‑circuit market is projected to surpass $50 billion by 2035, according to IDTechEx. The new programmable waveguide could accelerate this growth by reducing the number of discrete components required in a system.”

Further technical details can be found in the Nature publication “Programmable on-chip nonlinear photonics.” 

Two weeks ago, Cerebras Systems secured $1.1B and shortly after withdrew its IPO plans, only to clarify last week that the move was meant to update its financials and strategy before refiling, with the IPO still on track.

“Cerebras CEO Andrew Feldman admitted that his artificial intelligence chipmaker made a mistake last week when it didn’t immediately explain its decision to withdraw its registration for an initial public offering. […] ‘Given that the business has improved in meaningful ways we decided to withdraw so that we can re-file with updated financials, strategy information including our approach to this the [sic] rapidly changing AI landscape,’ Feldman wrote.”

Headlines


Last week’s headlines covered major semiconductor updates from new architectures to EU policy moves, advances in quantum and photonic computing, progress in neuromorphic systems, next-gen data center plans, and new cloud and AI partnerships.

⚛️ Quantum

⚡️ Photonic / Optical

🧠 Neuromorphic

💥 Data Centers

If you’d like to learn more about data centers in space, check out our interview with Starcloud!

☁️ Cloud

🤖 AI

Anthropic and IBM Partner in Bid for AI Business Customers (The Wall Street Journal – Paywall)

Readings


This week’s reading list features AI-driven chip trends, quantum use cases for memristors, programmable photonic architectures, neuromorphic applications in sensing, and the next wave of connectivity with 5G-A and 6G.

🦾 Semiconductors

⚛️ Quantum

⚡️ Photonic / Optical

🧠 Neuromorphic

💥 Data Centers

The Data Center Dividend (McKinsey) (5 mins)

Top 10: Trends in Cloud Computing (Technology Magazine) (21 mins)

📡 Connectivity

5G-A Evolution & Why It Matters (Counterpoint Research) (12 mins)

Funding News


Last week’s funding leaned toward early-stage rounds across AI, cloud, semiconductors, and quantum. The clear outlier was Reflection AI’s $2B Series B, highlighting the widening gap between large platform bets and smaller infrastructure plays.

Amount

Name

Round

Category

$2.6M

Supermemory

Seed

AI

$6M

Unikraft

Seed

Cloud

$6.8M

PEAK:AIO

Seed

Semiconductors

£7.5M

Sitehop

Series A

Quantum

$25M

Quilter

Series B

Semiconductors

$25M

Tigris

Series A

Cloud

$50M

RealSense

Series A

Vision Hardware

$2B

Reflection AI

Series B

AI

Undisclosed

Accelsius

Venture Round

Data Centers

Bonus: When Chips Pay for Themselves

The AI chip race just got very circular: OpenAI is buying billions worth of AMD GPUs, using AMD’s own stock to pay for them. The deal gives OpenAI up to a 10% stake in AMD and secures AMD a flagship customer in the AI boom. It’s a financial loop: chips, equity, and hype feeding back into each other, all while powering OpenAI’s 23-gigawatt data-center buildout.

More articles on the circular deals among OpenAI, NVIDIA and AMD:

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