QiB2: Two ways to couple qubits, on one chip.
A tunable-coupler pair, a fixed-coupler pair and three calibration qubits. For studying two-qubit gates, building calibration tools, and teaching.
- Box20 · Gold-plated OFHC copper
- 20 × Radial SMPM
Average T1
≤140 µs
Up to 223 µs highest observed · datasheet v2.2
- Qubits
- 7: two coupled pairs + 3 single
- Lines you need
- Readout + 6 drive + 4 flux
- Package
- Box20, 20 × SMPM
Specifications
From the QiB2 datasheet v2.2. Meas. marks a value measured on a device.
QiB2 specifications
QiB2-015- Coupling type I
- 2 fixed-frequency qubits + tunable coupler
- Coupling type II
- 2 tunable qubits + fixed resonator coupler
- Calibration points
- 2 bare resonators; fixed qubit via resonator; fixed qubit with drive line; tunable qubit with drive + flux
- Frequencies
- Qubits 3–5.5 GHz; resonators/couplers 4.5–8 GHz; two-qubit gate frequencies <2 GHz
- T1
- Up to 140 µs average; up to 223 µs highest observed
- Measured
- T2 echo
- Typically 1–2 × T1
- Measured
- Resonator Qi
- ≳1×106 at single-photon power
- Measured
- Package
- Box20, 20 SMPM
- Reference device
- QiB2-015
- Measured
Reference device
Datasheets show a measured reference device. Individual characterisation on request.
All elements
| Element | fq GHz | fr GHz | T1 avg µs |
|---|---|---|---|
| Q1Fixed qubit | 3.85 | 6.30 | 84 |
| Q2Fixed qubit | 4.65 | 7.15 | 39 |
| C1-2Coupler | 5.58 | 7.40 | 25 |
| Q3Tunable qubit | 4.63 | 7.28 | 20 |
| Q4Tunable qubit | 5.13 | 7.89 | 22 |
| C3-4Coupler | – | 4.77 | – |
| Q5Fixed qubit | 3.93 | 6.43 | 55 |
| Q6Tunable qubit | 4.12 | 6.72 | 47 |
| Q7Fixed qubit | 3.19 | 5.00 | 82 |
| R1Bare resonator | – | 5.44 | – |
| R2Bare resonator | – | 6.94 | – |
Q1–Q2: fixed pair through tunable coupler C1-2. Q3–Q4: tunable pair through fixed coupler C3-4. Q5 fixed with drive line, Q6 tunable with drive + flux, Q7 fixed via resonator.
What you can do with it
Study the two-qubit gates a tunable coupler and a fixed coupler each allow
Build and test calibration tools
Teach superconducting qubits with a real device
Installation
Box20 port map and mounting as in the datasheet.
- Lines you need
- Readout + 6 drive + 4 flux
- Connectors
- 20 × Radial SMPM; 6-inch SMPM–SMA cables on request
- Temperature
- <50 mK fixed elements; ~10 mK tunable
- Mounting
- M3 screws to the coldest plate
- Shielding
- Thermal + infrared shield inside a magnetic shield
- Port map
- In the datasheet v2.2 (PDF)
In the classroom
The Niels Bohr Institute has used QiB2 in its Quantum Training Lab since 2024.
Plug'N'Teach, the complete teaching labWe have been using the QiB2 device in the Quantum Training Lab at the Niels Bohr Institute since 2024. The device is well suited for this purpose since it allows for the evaluation of different properties of superconducting qubits.
The Qubit-in-a-Box family
Compare all three- QiB0
Four qubits for validating your setup.
- Qubits
- 4 fixed-frequency
- T1
- 90–130 µs avg, up to 256 µs
- Package
- Gold-plated copper, 2 × SMA
- QiB1
Six qubits, three levels of control.
- Qubits
- 6: fixed and tunable, two transmon styles
- T1
- Reference device 56–151 µs
- Package
- Box20, 20 × SMPM
- QiB2This page
Two ways to couple qubits, on one chip.
- Qubits
- 7: two coupled pairs + 3 single
- T1
- Up to 140 µs avg, up to 223 µs
- Package
- Box20, 20 × SMPM
Ordering
- Price
- from €19,800
- Lead time
- 6–8 weeks
- North America
- Order through our distributor, Quantum Microwave.
Datasheet
Shipping and export control
Our quantum devices are EU dual-use items (category 3A001). Every order needs a signed End-User Statement before shipping. Within the EU, and to Australia, Canada, Iceland, Japan, Liechtenstein, New Zealand, Norway, Switzerland, the UK and the US, no individual licence is needed. Anywhere else needs an export licence, which adds time, so tell us your destination early and we'll start the paperwork with you.