Useful Quantum Computing

Pete Shadbolt

Google Sycamore

54 qubits × 20 clock cycles~100 ft21 million samples200 seconds

Oak Ridge Summit (Schrödinger-Feynman)

54 qubits × ~ 20 clock cycles6,000 ft2

1 million samples10,000 years?

Oak Ridge Summit (Schrödinger)

54 qubits × ~ 20 clock cycles6,000 ft2128PiB SSDArbitrarily many samples6 days

100 101 102 103 104 105 106 107 108

10-1

10-2

10-3

10-4

Error Correction Threshold

GoogleResearchDirection

Useful errorcorrected QC

Near-termapplications

Classicallysimulatable

Number of Qubits

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Figure credit:

108

𝑁𝑁𝑝𝑝ℎ𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦 ~ 10,000 × 𝑁𝑁𝑦𝑦𝑙𝑙𝑙𝑙𝑦𝑦𝑦𝑦𝑦𝑦𝑦𝑦

PsiQ P1*

100 qubits × 1 million clock cyclesFew thousand ft21 million physical qubitsMinutes

Oak Ridge SuperSummit *

100 qubits × 1 million clock cycles6,000 × 2100-54 = 400,000,000,000,000,000 ft2

128 × 2100-54 = 9,000,000,000,000,000 PiB SSDA very long time

❄️Cooling power

⚡️Control electronics

📞📞Connectivity

🏭🏭Manufacturability

1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

10mK 10K - Cryostat 10K - Cryoplant

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1.E-03

1.E-02

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

1.E+08

1.E+09

Google Sycamore PsiQ Vega PsiQ Polaris

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