256 quantum bits! Amazon Braket Goes Live with First Neutral Atom Quantum Processor

On November 1, Amazon's quantum computing service Amazon Braket announced [1] the launch of Aquila, a new neutral-atom quantum processing unit (QPU) with up to 256 quantum bits from QuEra Computing. It will be available for ten hours on Tuesdays, Wednesdays and Thursdays. The processor can be programmed with the AWS Braket SDK, and soon QuEra's own Bloqade software platform, based on the Julia programming language, will also support Aquila.

01A new simulation paradigm for quantum computing

Aquila magneto-optical trap in QuEra's facility.

QuEra's QPU is the first device on Amazon's Braket to be able to perform the "Analog Hamiltonian Simulation (AHS)" paradigm of quantum computing.

AHS refers to the ability to encode a problem of interest into a mathematical object called a Hamiltonian. The Hamiltonian represents the energy level of a quantum system, such as the interacting spins (spins) on a lattice. The computer is then tuned so that it directly simulates the continuous time evolution of the quantum system at that Hamiltonian quantity.

In a traditional gate-based quantum computer, the user can directly program the gates acting on the quantum bits. Quantum processors, such as the Oxford Quantum Circuit, or the Rigetti device on Amazon Braket operate this way, with quantum bits consisting of the ground and excited states of an anharmonic oscillator. the QuEra QPU operates by trapping atoms with a laser, arranging them in a programmable one- or two-dimensional layout, and inducing inter-atomic interactions via van der Waals forces. Quantum bits consist of the ground state of an atom and a highly excited state, the so-called Riedberg state. By exciting atoms from the ground state to the excited state, QuEra's QPU enables a phenomenon known as Rydberg blocking, where the quantum states of neighboring quantum bits are fixed by the state of the controlling quantum bit. In addition, customers can dynamically adjust the driving field parameters to control the states of the quantum bits and their interactions.

With the launch of the QuEra QPU on Amazon Braket, researchers can use Amazon Braket, using Aquila, to study hybrid algorithms.

02Aquila: Neutral Atom Quantum Processing Unit

The QuEra QPU is a special-purpose device that swaps the ability to perform general-purpose or gate-based computing with the ability to efficiently solve specific tasks.

QuEra's technology is based on rubidium atoms to form quantum states. It has a number of advantages.

Because the atoms are neutral, rather than charged like those in an ion trap, they can be placed more closely together to obtain smaller physical parts.

The atoms are placed on the substrate with laser "optical tweezers" and can be placed in any topology. This allows the end user to create a customized physical configuration of the atoms for their specific problem.

Topologies are not limited to fixed two-dimensional arrays or heavy hexagonal structures. Unwanted atoms do not have to be placed on a substrate, providing flexibility for configuration problems.

The flexible atomic arrangement and the tunability of the optical controls allow Aquila to achieve a rich class of Hamiltonian quantities. Customers can explore the static and dynamic properties of these sub-Hamiltonian quantum states through adiabatic or adiabatic quantum evolution. Although the neutral atom processor can operate in either digital or analog mode, this initial version of Aquila supports only analog mode.

So far, the Hamiltonian equations implemented by the QuEra QPU have been used to study several scientific problems of interest in condensed matter and quantum many-body physics. One example is the observation of the emergence of the spin-liquid phase, a state of matter with non-local, topological order. These phases are difficult to study numerically because of the system scale required to demonstrate nonlocal order. the QuEra QPU allows customers to program complex lattice geometries, such as Kagome lattices with up to 256 quantum bits, a system scale large enough to explore these new states.

An example of the versatility of the QuEra QPU. Customers can program virtually arbitrary arrangements of atoms to study a wide range of problems from quantum many-body physics to graphical problems.

As shown above, Aquila users are not limited to a specific lattice geometry or to arranging quantum bits into any regular pattern. In addition to strongly correlated multi-particle systems, scientists were able to demonstrate that neutral atom processors like Aquila are suitable for arranging atoms in graphical patterns and solving certain combinatorial optimization problems. That is, these machines can encode the maximum independent set (MIS) problem, which has a wide range of applications in optimization for resource allocation, network design, etc. The MIS problem can be cast as a variational problem that can be computed using an iterative optimization loop that combines a mix of quantum and classical operations.

03Amazon Braket: a cloud service platform for quantum computing

In fact, in 2021, Amazon created true random numbers using the Rigetti and IonQ quantum processors on its Braket quantum computing service platform. In recent years, Amazon and its AWS cloud computing division have made several significant investments in quantum computing. Through Amazon Braket, the company provides developers with access to quantum computers from IonQ, Oxford Quantum Circuits, Rigetti and D-Wave, as well as other software tools and simulators.

How Braket works: A fully managed quantum computing service designed to help accelerate scientific research and software development in quantum computing.

Braket's existing customers.

This time, the neutral atom QPU Aquila, available on Amazon Braket, uses an intrinsic quantum system - atoms on a tunable lattice - to be able to solve specific problems of interest to a wide range of researchers; Aquila is now available for use in the Northern Virginia region of the United States.

The academic community has been raving about it. Ignacio Cirac, director and head of the Theory Department at the Max Planck Institute for Quantum Optics (MPQ), said [2], "Until we achieve a fault-tolerant general-purpose quantum computer, special-purpose analog quantum devices may outperform classical computing in directly simulating other quantum systems. In the theory department of MPQ, we are excited about the QuEra device launched on Amazon Braket, which allows our research team to experiment and pursue new ideas in the field of analog quantum simulations."

Reference links:

[1]https://aws.amazon.com/cn/blogs/quantum-computing/amazon-braket-launches-aquila-the-first-neutral-atom-quantum-processor-from-quera-computing/

[2]https://quantumcomputingreport.com/quera-launches-their-256-qubit-analog-quantum-processor-on-aws/