In recent years, the field of quantum computation is experiencing an impressive awakening, represented in many startup companies working on related technologies. These technologies revolve around storing and manipulating information encoded not in bits (1s and 0s), but in quantum states – where combinations of 0s and 1s are allowed.

Today, the main problem restricting quantum technologies is that the quantum bits encoding the quantum states (qubits) are fragile and accumulate errors as a result of the surrounding noise. This results in highly error-prone computation, impeding any actual application of quantum computation.

How would one solve this conundrum? How would one create error-free quantum information?

Here, a new idea comes into the picture. This idea is based on states called “topological states”, which are the quantum analog of locking a bicycle with a lock. The lock has two states: either open or closed. For two decades, theoretical physicists have brought up and fine-tuned this idea. According to the theories, if one could manufacture these mysterious topological states, it would be possible to encode logical operations by rotating them one around the other in space. With a clockwise turn – the lock is open, and with an anti-clockwise turn - the lock is closed.

So, theoretical physicists present us with two challenges:

1. Create a topological state.
2. Manipulate the state in space that allows encoding of mathematical operations.

How would we face these two challenges?

One candidate would be an object named “Superconducting Vortex”. A superconducting vortex is a single packet of magnetic flux penetrating a superconductor. According to researchers, vortices should host these topological states in a specific type of superconductor.

For a practical “Topological Quantum Computer”, there are still a few technological barriers. The first is that until now, there has been no ability to manipulate vortices on a microchip quickly and reliably. The absence of such ability is the barrier that a team of researchers from the Hebrew University led by Dr. Yonathan Anahory, Prof. Hadar Steinberg, and their student Itai Keren from the Racah Institute of Physics has overcome. They solved this issue by designing an array of loops that carry current and thus control the vortices reliably at the nanoscale. This is a breakthrough, enabling the next phase – building a device consisting of a detection mechanism to detect the vortices' quantum state. It might lead to a proof of concept on the path to the first topological quantum computer, which should be noise tolerant. 

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