An innovative approach to qubit design results in a new framework that creates highly customized quantum devices.
Quantum science has the potential to revolutionize our lives. Quantum computers promise to solve difficult problems today. Quantum networks may be used as hackerproof information highways.
These forward-looking technologies largely depend on the qubit, the fundamental component of quantum systems. Qubit research challenges designing qubits that can be customized to fit all types of communication, sensing, and computational devices.
Scientists have made a significant step towards the development of tailor-made qubits. A team of MIT, Columbia University and the University of Chicago published a paper in the Journal of the American Chemical Society. It shows how a specific molecular family of qubits can finely tune over a wide spectrum. This is similar to turning a dial on a wideband radio.
They also outline the design features that precisely control these quantum bits.
This new platform is ideal for designing qubits. “We can use our predictable and controllable, tunable strategy for creating a new quantum systems,” explained Danna Freedman (MIT professor of chemistry, co-author of this study). “We have demonstrated the wide range of tunability that these design principles can be used to create new quantum systems.”
Q-NEXT partially supports the work of the U.S. Department of Energy’s National Quantum Information Science Research Center, led by Argonne National Labor.
Researchers are focusing on a particular group of molecules. They have a central chromium-atom surrounding four hydrocarbon molecules, forming a pyramid-like structure.
The molecular qubit benefit
The qubit is the quantum equivalent to the traditional computing bit. It can take physical forms, such as an atom in a crystal or an electric circuit. You can also make it yourself.
A molecular qubit has the advantage that it can be built from the bottom up. Scientists have the freedom to adjust the qubit’s functions.
Leah Weiss is a postdoctoral researcher at the University of Chicago and co-author of the study.
The information of a molecular qubit is stored in its spin. This property is found in atomic-level materials. Scientists can tune the arrangement of electrons in a molecule to create spin. The qubit encodes the information in its spin. The spin-encoded data is then converted into photons to be read.
Different wavelengths of photons work better for different applications. One wavelength might be better for biosensing, while another is best for quantum communication.
The ligand is the thing.
The ligand field strength is a key tuning dial for molecular qubits. It measures the strength of the bonds that connect the central metal atom with the surrounding hydrocarbons.
“The ligand is fundamentally all.” “We can control how the ligand environment affects the spin and rationally regulate where the emitted photos end up,” stated Dan Laorenza (MIT graduate student and the lead author of this paper.”
Researchers proved that they were able to tune these bonds with remarkable precision. Researchers also demonstrated that the ligand field strengths could be adjusted over a broad spectrum. Meanwhile, Columbia researchers performed quantum mechanical simulations that provided insight into the role of ligands in controlling the molecule’s electronic properties.