Using Qubits and Quantum Computers to Find Dark Matter
Searching for Dark Matter With Quantum Computers, One Blip of Light at a Time
Excerpts and salient points ~
+ In 2007, physicist David Schuster, then at Yale, asked his advisor whether qubits could serve as useful detectors for astronomy—after all, the core component of the quantum computer, the qubit, is essentially just a super-sensitive light detector. But his advisor responded that the device wouldn’t work for astronomy, since it wouldn’t detect photons unless they magically appeared inside of the cavity housing the qubit. “It was sensitive, but only good at detecting things in the cavity,” Schuter said.
Pursuing these experiments has pushed these two fields forward hand-in-hand, Fermilab deputy chief technology officer Anna Grasselino told Gizmodo. “I would say the technology is pushing forward the search, but the search itself is giving us motivation to further explore technology in the quantum regime,” she said. Quantum technologies for computing and for axion hunting share a related but ultimately different goal, which pushes the field forward overall; Dixit said that most companies working on building quantum computers don’t think about qubit errors at quite the same level that the QISMET team must—they require some of the lowest error rates.
+ Quantum computers in the technical sense are only computers when you use them to perform computations; otherwise, their qubits are just systems of artificial atoms. The most popular qubit architecture consists of loops of superconducting wire through which current travels without resistance, broken up by a small piece of insulator in a region called a Josephson junction. Each of these loops obey the same rules of quantum mechanics that an electron would in its orbit around an atom: in the presence of a photon of the right frequency, they enter an excited state, represented in the loop as a tiny amount of current through the wire. But unlike an atom’s electron, qubits light up in response to a range of photon frequencies rather than individual frequencies like an atom, Bowring explained.
+ [O]nce QISMET is up and running, it will demonstrate a real benefit of quantum technology over existing sensing solutions, likely before companies like Google and IBM’s quantum computers have useful computing applications. The work demonstrates the importance of basic research in pushing the boundaries of technology to solve problems only physicists have, like how to find a subatomic particle that might not exist. The experiment’s scientists don’t endeavor to develop a product that might one day generate a profit; they’re driven by the powerful, mysterious force of curiosity.
Content may have been edited for style and clarity.