The Josephson Junction: The Tiny Gap That Makes a Superconducting Qubit Possible
Peer inside a superconducting quantum processor from IBM, Google, or Rigetti and you will find, at the core of every qubit, a device so small you woul...
The Barium Bet: Why Ion-Trap Machines Are Switching Atoms
Every trapped-ion quantum computer starts with a choice most people never see: which atom to trap. The qubit is not built, it is borrowed from nature,...
The Calibration Treadmill: Why Quantum Computers Need Constant Tuning
Walk into a lab that runs a superconducting quantum computer and you will not find a machine that boots up once and stays ready. The processor drifts....
The Fluxonium Qubit: The Slower Cousin That Refuses to Forget
Walk into almost any lab building a superconducting quantum computer and you will find the same workhorse qubit: the transmon. It is the design behind...
The Cat Qubit Bet: Building Error Resistance Into the Hardware
Quantum computers make mistakes constantly. A single qubit can lose its delicate state in microseconds, and the standard fix is brute force: surround...
The Wiring Bottleneck: Quantum Computing's Unglamorous Control Problem
Photographs of quantum computers usually show the same thing: a golden chandelier of plates and tubes hanging inside a refrigerator, looking like a st...
The Magic State Factory: The Expensive Gate a Quantum Computer Must Brew
Ask a quantum architect what will fill a future fault-tolerant machine, and you might expect an answer about qubits or wiring. Increasingly the honest...
The Noise Dial: How a Quantum Computer Fakes a Cleaner Answer
Ask a quantum computer to do anything useful right now and it will hand you back a number that is wrong. Not catastrophically wrong, but polluted by t...
The Benchmark Wars: How to Actually Measure a Quantum Computer
Ask a quantum computing company how good its machine is and you will rarely get a simple number. You will get several, and they will not agree with ea...
The Benchmark Wars: Why Quantum Computers Can't Agree on a Yardstick
Ask a quantum computing company how good its machine is and you will get a number. The trouble is that no two companies quote the same number. One bra...
The Transmon Workhorse: Why Superconducting Circuits Dominate Quantum Computing
If you log into a quantum computer through a cloud service from IBM, Google, or Rigetti, odds are you are talking to a chip made of superconducting ci...
The Wiring Wall: Why a Quantum Fridge Runs Out of Cables Before Qubits
Look inside the photographs quantum computing companies love to publish and you will see a gleaming golden chandelier hanging in a laboratory. It look...
The Transmon: The Charge-Shy Qubit That Runs the Cloud
If you log into a quantum computer today through IBM's cloud, Google's lab, or a Rigetti processor, odds are you are talking to a transmon. It is the...
The Calibration Treadmill: Why a Quantum Computer Is Never Done Being Tuned
Picture a piano that slips out of tune not once a year but every few hours, with 100 keys that each drift in their own direction. Now imagine you cann...
The Unimon: Finland's Qubit That Rethinks the Transmon
Most superconducting quantum computers run on a qubit called the transmon, a design so dominant that it powers nearly every machine IBM, Google, and R...
The Decoder Bottleneck: The Classical Brain Behind Quantum Error Correction
Most stories about quantum error correction focus on the qubits: how many you need, how to wire them into a surface code, how often they fail. But the...
The Analog Shortcut: Pasqal's Bet on Atoms That Skip the Gates
Most quantum computers work the way a classical computer does, at least in spirit. You break a problem into a sequence of discrete logic gates, apply...
The Grid State: Hiding a Qubit in the Ripples of a Cavity
The standard recipe for a fault-tolerant quantum computer is brute force. Take a hundred or a thousand shaky physical qubits, wire them into a lattice...
The National Lab Testbed: How Governments Became Quantum's Proving Ground
When a quantum computing company shows off a new processor, the demonstration usually comes with a polished interface and a fixed set of operations. Y...
The Shot Count: Why a Quantum Computer Runs the Same Program 10,000 Times
Feed a problem to a laptop and it gives you one answer. Feed the same circuit to a quantum computer and it hands you a pile of them, often ten thousan...
The Tunable Coupler: The Switch That Turns Qubit Chatter On and Off
Two qubits sitting side by side on a superconducting chip have a problem: they can hear each other whether you want them to or not. Physics does not c...