Quantum Computing Hardware
Which is the most appropriate comparison of superconducting and trapped-ion platforms?
- AIn superconducting platforms each qubit is an atom, so there is no fabrication variation at all
- BSuperconducting platforms have fast gates but connect qubits mainly to their neighbors; trapped-ion platforms have slower gates but can easily connect any ions in the same trap directly
- CTrapped-ion platforms require a dilution refrigerator at about 10 mK, while superconducting platforms operate at room temperature
Show answer and explanation
Answer: B. Superconducting platforms have fast gates but connect qubits mainly to their neighbors; trapped-ion platforms have slower gates but can easily connect any ions in the same trap directly
Two-qubit gates in superconducting platforms are fast, about tens to hundreds of ns, but the qubits are coupled through circuits on the chip, so they connect mainly to neighboring qubits. Gates in trapped-ion platforms are generally about a few µs to hundreds of µs, often two to three orders of magnitude slower than superconducting gates, but ions in the same trap can perform gates in any combination through their shared vibrational motion. Superconducting qubits are fabricated circuits, so their frequencies vary with tiny differences in the junctions, whereas ions of the same species are all identical. Superconducting platforms need a dilution refrigerator, and trapped-ion platforms need an ultra-high vacuum and lasers.
- A. Having identical atoms as qubits is a strength of trapped ions. Superconducting qubits are fabricated circuits, so their frequencies and other properties vary.
- B. Correct. There is a trade-off between gate speed and how easily qubits can be connected.
- C. It is the other way around: superconducting platforms require a dilution refrigerator, while trapped-ion platforms use ultra-high vacuum and laser cooling.