BAR-ILAN INSTITUTE OF NANOTECHNOLOGY & ADVANCED MATERIALS | 2019 ANNUAL REPORT

these two technologies demands a wide range of expertise, and to that end, I established several important research collaborations throughout the world.” Dr. Stern collaborates with many research groups in Israel, Europe, and Australia. One of his most recent collaborations, established through BINA, is with Dr. Juha Muhonen from Jyväskylä University in Finland. In the heart of these collaborations is Dr. Stern’s laboratory, with its expertise in superconducting circuits. “A hybrid system like the one we are trying to build now would keep quantum information safe and allow us to couplemultiple qubits together. This could dramatically influence our ability to progress towards the development of a quantum computer.” Bit vs. Qubit Over one hundred years have passed since physicists discovered that the microscopic world does not operate under the laws of classical physics. The behavior of the microscopic world goes against our intuition. For example, a particle, like an electron, can simultaneously be in two different positions, in a so-called “superposition state”. The quantum computer exploits this strange property of nature: a quantum register made of qubits can store information in a superposition state. This property enables the quantum computer to perform calculations exponentially faster than a classical computer. Another interesting property of the quantumcomputer is that, theoretically, it does not require energy to operate. A bit operates like a bistable system stabilized by dissipation: energy is needed to change the state of the system from zero to one. Friction enables the operation of the bit, but also creates so much heat that “we could use it in place of a heater,” says Dr. Stern. An estimated 17 billion connected devices operate globally and are a grave toll on the energy resources across the world. Quantum reality starts where friction ends; no friction means calculation is possible – at least theoretically – with no energy consumption. Investing Lots of Energy to Create a Non-Energy-Consuming Quantum Computer Excitingly, just a couple of months ago, Google announced that they achieved quantum supremacy with their Sycamore quantum processor. This processor contains only 53 qubits, which, in three minutes, solves a calculation that would take 10,000 years to solve with a classical supercomputer. However, in order to construct a proper quantum computer, at least 1,000 qubits would need to be coupled together and herein lies the problem. “In a regular computer, for every one billion bits, we get close to 100% calculation success. In contrast, one qubit has 99.5% success. Consequently, increasing to 1,000 qubits to achieve the hypothetical quantum computer, decreases the validity to only 4.25% – no success at all. In other words, every added qubit exponentially decreases the reliability of the calculation. In order to solve this problem we would need to implement correction codes, which have not yet been developed,” concludes Dr. Stern. Dr. Michael Stern, Head of the Quantum Nanoelectronics Laboratory Dr. Michael Stern joined the Physics Department and the Bar- Ilan Institute of Nanotechnology and Advanced Materials (BINA) in 2015 and established the new Quantum Nanoelectronics Laboratory, which focuses on hybrid quantum systems. Dr. Stern graduated from École Centrale Paris, and after founding a start-up company and working in the industry, he returned to academia and obtained his PhD at the Weizmann Institute of Science. He conducted his post-doctorate in mesoscopic physics, working on superconducting circuits in the Quantronics group at Paris- Saclay. Dr. Stern is a member of the QUEST Center – QU antum E ntanglement in S cience and T echnology – established at Bar- Ilan University four years ago. The Center brings together both theorists and experimentalists, as well as physicists, engineers, and mathematicians who are active in research related to quantum entanglement, enabling them all to operate under one roof, giving their work the added value of collaboration. 17