At an Intel Labs virtual event today, Intel unveiled Horse Ridge II, its second-generation cryogenic control chip, marking another milestone in the company's progress toward overcoming scalability, one of quantum computing's biggest hurdles. Building on innovations in the first-generation Horse Ridge controller introduced in 2019, Horse Ridge II supports enhanced capabilities and higher levels of integration for elegant control of the quantum system. New features include the ability to manipulate and read qubit states and control the potential of several gates required to entangle multiple qubits.

"With Horse Ridge II, Intel continues to lead innovation in the field of quantum cryogenic controls, drawing from our deep interdisciplinary expertise bench across the Integrated Circuit design, Labs and Technology Development teams. We believe that increasing the number of qubits without addressing the resulting wiring complexities is akin to owning a sports car, but constantly being stuck in traffic. Horse Ridge II further streamlines quantum circuit controls, and we expect this progress to deliver increased fidelity and decreased power output, bringing us one step closer toward the development of a 'traffic-free' integrated quantum circuit."-Jim Clarke, Intel director of Quantum Hardware, Components Research Group, Intel.

A team of scientists at the MPQ realizes a first elementary quantum network based on interfaces between single atoms and photons. Whether it comes to phoning a friend or to using the internet - our daily communication is based on sophisticated networks, with data being transferred at the speed of light between different nodes. It is a tremendous challenge to build corresponding networks for the exchange of quantum information. These quantum networks would differ profoundly from their classical counterparts: Besides giving insights into fundamental questions in physics, they could also have applications in secure communication and the simulation of complex many-body systems, or they could be used for distributed quantum computing. One prerequisite for functional quantum networks are stationary nodes that allow for the reversible exchange of quantum information.

A major breakthrough in this field has now been achieved by scientists in the group of Professor Gerhard Rempe, director at the Max Planck Institute of Quantum Optics and head of the Quantum Dynamics division: The physicists have set up the first, elementary quantum network (Nature, DOI: 10.1038/nature11023, 12 April 2012). It consists of two coupled single-atom nodes that communicate quantum information via the coherent exchange of single photons. "This approach to quantum networking is particularly promising because it provides a clear perspective for scalability", Professor Rempe points out.

A multi-purpose optical chip which generates, manipulates and measures entanglement and mixture - two quantum phenomena which are essential driving forces for tomorrow's quantum computers - has been developed by researchers from the University of Bristol's Centre for Quantum Photonics. This work represents an important step forward in the race to develop a quantum computer.

The fundamental resource that drives a quantum computer is entanglement - the connection between two distant particles which Einstein famously called 'spooky action at a distance'. The Bristol researchers have, for the first time, shown that this remarkable phenomenon can be generated, manipulated and measured entirely on a tiny silica chip. They have also used the same chip to measure mixture - an often unwanted effect from the environment, but a phenomenon which can now be controlled and used to characterize quantum circuits, as well as being of fundamental interest to physicists.