DATE2023.12.05 #Press Releases

Quantum computers compared

Using simulations, researchers compared the performance of a superconducting quantum computer and an ion trap quantum computer. 
 
Dec 05, 2023 
 
Quantum computers will be the future of computation. They use qubits, which are superpositions of 0 and 1, rather than bits, which are discrete 0’s and 1’s used in conventional computers. Researchers Erik Lötstedt and Kaoru Yamanouchi from the University of Tokyo used simulations to compare two different types of quantum computers: a superconducting quantum computer, where qubits are implemented as superconducting circuits, and an ion trap quantum computer, where qubits are realized as atomic ions trapped by radio-frequency electric fields.  
 
The operation of quantum computers is subject to various errors arising from environmental interactions. The error in the qubit information in quantum computers is a challenge facing the field. Armed with the knowledge of error mitigation and quantum computation, the scientist duo used simulations to assess the performance of the two quantum computer types.  
 
They found that both computers could accurately simulate the dynamics of a spin system. While the superconducting quantum computer required error suppression, the ion trap quantum computer did not, although it took 200 times longer to execute one quantum circuit. So accurate calculations take longer time and faster calculations lead to less accuracy. The findings will help select the suitable device depending on the computational tasks. 
 
Figure: Trapped-ion type and superconducting qubit type quantum computers. Photo credits: @Quantinuum (left) and @IBM (right).

For more details, please read the article:   
Erik Lötstedt and Kaoru Yamanouchi 2023. Comparison of current quantum devices for quantum computing of Heisenberg spin chain dynamics. Chemical Physical Letters. DOI: 10.1016/j.cplett.2023.140975.