The new hardware, says the company, features 32 perfect qubits with low gate errors, giving it an expected quantum volume greater than 4,000,000 – well above other current quantum computing systems using this metric. The new system consists of perfect atomic clock qubits and random access all-to-all gate operations for efficient software compilation of applications.
“In a single generation of hardware, we went from 11 to 32 qubits, and more importantly, improved the fidelity required to use all 32 qubits,” says IonQ CEO & President Peter Chapman. “Depending on the application, customers will need somewhere between 80 and 150 very high fidelity qubits and logic gates to see quantum advantage. Our goal is to double or more the number of qubits each year. With two new generations of hardware already in the works, companies not working with quantum now are at risk of falling behind.”
IonQ Co-Founder & Chief Scientist Chris Monroe says, “The new system we’re deploying today is able to do things no other quantum computer has been able to achieve, and even more importantly, we know how to continue making these systems much more powerful moving forward. With our new IonQ system, we expect to be able to encode multiple qubits to tolerate errors, the holy grail for scaling quantum computers in the long haul.”
The company’s “trapped-ion” approach to quantum computing traps individual atoms in 3D space and then use lasers to do everything from initial preparation to final readout. The system’s qubits are ionized ytterbium atoms, and once prepared in a particular stable quantum state, they can remain in that state for very long periods of time. They’re so consistent, says the company, they’re used in one of the most accurate atomic clocks ever built.
Once the atom is turned into an ion, a specialized chip called a linear ion trap is used to hold it precisely in 3D space. This small trap features around 100 tiny electrodes precisely designed, lithographed, and controlled to produce electromagnetic forces that hold the ions in place, isolated from the environment to minimize environmental noise and decoherence.
Any number of ions can be loaded into a linear chain, resulting in on-demand reconfigurability that, says the company, allows it to theoretically create anything from a one-qubit system to a 100+ qubit system without having to fabricate a new chip or change the underlying hardware. To prepare the ions to perform quantum computations, they are first cooled and then initialized into a well-defined “zero” state.
Computation uses a series of operations called gates to manipulate the qubits’ state, first encoding and then operating on the information to be calculated. To perform these gates, says the company, its uses an array of individual laser beams, each imaged onto an individual ion, plus one “global” beam. The interference between the two beams produces a beat note that is at exactly the necessary energy to kick the qubits into a different state.
Once the computation has been performed, reading the answer from the ions is done by shining a resonant laser on all of them at the same time. This process collapses any complex quantum information that’s been created and forces each qubit into one of two states.
Collecting and measuring this light, says the company, allows it to simultaneously read the collapsed state of every ion – one of the states glows in response to the laser light, the other does not. This is interpreted as a binary string, where each glowing atom is a one, and each dark atom is a zero.
“To successfully hold complex quantum information, qubits can’t interact with anything,” says the company. “A single stray hydrogen atom colliding with an ion can spoil the whole thing, collapsing delicate states, making ions switch places, or knocking the chain out of the trap entirely. So, we put the trap inside an ultra-high vacuum chamber, pumped down to around 10-11 Torr. At this pressure, there are about one hundred trillion times fewer molecules per cubic inch than the air you’re currently breathing.”
Once everything’s in the chamber, the whole assembly goes in an even larger enclosure with a variety of electrical, mechanical, and optical control systems. Then, says the company, it all gets hooked to a classical computer running the company’s custom control software, and after a great deal of calibration, it’s a fully functioning quantum computer, ready to perform gates and run algorithms with world-leading fidelity.
The company has raised $84 million in funding, recently announcing new investment from Lockheed Martin, Robert Bosch Venture Capital GmbH (RBVC) and Cambium. Previous investors include Samsung Electronics, Mubadala Capital, GV, Amazon, and NEA.
Francis Ho, Senior Vice President and Managing Director, Samsung Catalyst Fund says, “IonQ represents one of the most promising approaches to quantum computing that is both scalable and does not require any significant materials science or manufacturing breakthroughs. The company’s unique combination of academic research and experience plus proven performance has led to their system demonstrating industry leading performance and helping break new ground in quantum computing.”
The new system will be first available via private beta, and then commercially available on Amazon Braket and Microsoft’s Azure Quantum.
Honeywell to release ‘world’s most powerful’ quantum computer
IBM on ‘quantum supremacy’
AWS quantum computing service now generally available
Microsoft announces cloud quantum computing service