superconducting qubits
The Cosmic Ray Strike: When One Particle Blanks a Whole Quantum Chip
RafayelQuantum error correction rests on a quiet assumption: that mistakes happen one qubit at a time, more or less at random, in scattered spots a code can...
The Quantum Interconnect: How Separate Chips Learn to Act as One
There is a quiet ceiling hanging over every superconducting quantum computer. You can etch more qubits onto a chip, but only up to a point. Push past...
The Purcell Filter: Reading a Qubit Without Letting It Leak Away
Every superconducting quantum processor faces the same awkward bargain. You cannot compute with a qubit you cannot measure, so you wire each qubit to...
The Tantalum Turn: The Metal That Doubled a Qubit's Memory
For most of the last two decades, superconducting qubits were built from a short list of metals: aluminum for the delicate Josephson junction, and nio...
The Quantum Amplifier: Hearing a Single Qubit Over the Roar
Ask a superconducting qubit whether it is a zero or a one, and it will tell you. The trouble is the volume. The signal that leaves a qubit during read...
The Tunable Coupler: The Dial That Switches Qubit Chatter On and Off
Two superconducting qubits sitting next to each other on a chip have a problem: they never stop talking. Because they share electromagnetic fields, th...
The Willow Chip: When More Qubits Made Fewer Errors
The central promise of quantum error correction has always come with an asterisk. In theory, you can spread one piece of quantum information across ma...
The Josephson Junction: The Weak Link at the Heart of a Qubit
Strip a superconducting quantum computer down to its most essential part and you arrive at something almost comically small: a gap in a wire. Two piec...
The Two Clocks: T1 and T2, the Timers Every Qubit Races
Ask an engineer how good a qubit is and, sooner or later, two numbers come up: T1 and T2. They sound like model names, but they are timers. Each measu...
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 Fab-1 Bet: Rigetti's Wager on Owning Its Own Qubit Foundry
Ask most people to name a quantum computing company and IBM or Google comes up first. Rigetti Computing is smaller and scrappier, but it made a decisi...
The Watt Gap: Why a Quantum Computer Sips Power a Supercomputer Guzzles
Walk into a room housing a superconducting quantum computer and your first assumption is probably wrong. The gleaming gold chandelier hanging inside t...
The Helium-3 Squeeze: The Rare Isotope Every Quantum Fridge Needs
Ask what limits the growth of a superconducting quantum computer and you will hear about qubit counts, error rates, and wiring. Further down the list,...
The Calibration Drift: Why a Quantum Computer Retunes Itself All Day
Buy a laptop and it behaves the same on Tuesday as it did on Monday. A quantum processor does not offer that courtesy. Left alone for a few hours, a c...
The Cat Qubit: The Bet That Half the Errors Just Vanish
Most qubits fight two enemies. A bit flip turns a 0 into a 1, and a phase flip scrambles the delicate relationship between the two states. Any error-c...
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 Millikelvin Machine: The Fridge That Keeps Qubits Cold Enough to Compute
Look at almost any photo of a superconducting quantum computer and you are not really looking at the computer. The chip itself is a fingernail-sized s...
The Annealer's Wager: D-Wave's Bet That You Don't Need Gates
Ask most people to picture a quantum computer and they imagine gates: crisp logical operations flipping and entangling qubits one step at a time, like...
The Heavy-Hex Lattice: Why IBM Wired Its Qubits Sparingly
Look at a photograph of one of IBM's superconducting quantum chips and you might expect a dense mesh, every qubit shaking hands with as many neighbors...
The Rabi Flop: How a Microwave Nudge Rotates a Qubit
Every quantum program, no matter how elaborate, bottoms out in the same humble act: pushing one qubit from where it is to where you want it. On a supe...
The Frequency Collision: When Two Qubits Land Too Close
Build a superconducting quantum processor out of fixed-frequency transmons and you inherit a problem that has nothing to do with quantum mechanics and...