您当前的位置: 首页 > 网页快照
Qubits measured in a different light - Nature Physics
Qubits measured in a different light
Download PDF
News & Views .
Published: 08 August 2022 .
QUANTUM INFORMATION
Qubits measured in a different light .
Richard Brierley 1 ? .
Nature Physics volume ?18 ,? page 859 ( 2022 ) Cite this article
1 Altmetric
Metrics details
Subjects .
Optomechanics .
Quantum information .
Qubits .
Superconducting devices .

You have full access to this article via your institution.

Download PDF
It is now quite common to read expansive visions of a quantum technological future where individual quantum computers are connected in a long-distance network. A reliable method of interconnecting quantum devices would make modular, distributed computing possible, and is a prerequisite to harness the advantages of quantum communication protocols. However, existing telecommunications networks use near-infrared wavelength photons, while the largest current quantum computers use superconducting microwave circuits. Robert Delaney and colleagues, writing in Nature , have now demonstrated that they can convert microwaves measuring a superconducting qubit into an optical signal ( Nature 606 , 489–493; 2022 ).
Credit: Springer Nature Ltd.
It is well established that optical nonlinearities can be used to transduce light from one frequency to another. When a photonic signal passes through a nonlinear medium and an intense ‘pump’ of coherent light is applied, then the signal can be upconverted to light with a frequency that is the sum of the signal and pump frequencies. Commonly used in classical photonics, this approach is also possible at the few-photon level. The challenge is to implement it without introducing so much noise to the signal source and the output that fragile quantum effects are lost or destroyed.
Along with several other groups, Delaney and co-workers have used optomechanical devices to develop a quantum transducer. Specifically, they coupled microwave and optical cavities to a silicon nitride mechanical resonator. Separate optical and microwave pump beams allowed them to convert between microwave photons and quantized mechanical oscillations, and then between the mechanical excitations and optical photons. Although this introduces an additional intermediary, the performance of these optomechanical devices is so high that this is an effective approach to convert microwave photons to optical ones.
Delaney and colleagues were able to use this approach to measure the quantum state of a superconducting qubit using the output optical light. Crucially, they showed that operating the transducer did not have a destructive effect on the performance of the qubit or its quantum state, so that further operations would be possible.
The performance of the device (pictured) does not yet allow for the conversion of non-classical states, which would be needed for a quantum network. But the team laid out a number of reasons why they are hopeful to reach the quantum regime. The continued progress in quantum transducers compatible with intermediate-scale superconducting quantum computers significantly improves the near-term prospects for developing quantum networks.
Author information .
Authors and Affiliations .
Nature Physics https://www.nature.com/naturephysics
Richard Brierley
Authors Richard Brierley View author publications
You can also search for this author in PubMed ? Google Scholar
Corresponding author .
Correspondence to Richard Brierley .
Rights and permissions .
Reprints and Permissions
About this article .
Cite this article .
Brierley, R. Qubits measured in a different light. Nat. Phys. 18, 859 (2022). https://doi.org/10.1038/s41567-022-01730-9
Download citation
Published : 08 August 2022
Issue Date : August 2022
DOI : https://doi.org/10.1038/s41567-022-01730-9
Share this article .
Anyone you share the following link with will be able to read this content:
Get shareable link Sorry, a shareable link is not currently available for this article.
Copy to clipboard
Provided by the Springer Nature SharedIt content-sharing initiative

You have full access to this article via your institution.

Download PDF
Associated Content .
Superconducting-qubit readout via low-backaction electro-optic transduction .
R. D. Delaney .
M. D. Urmey .
K. W. Lehnert .
Nature Article 15 Jun 2022
Advertisement
Advertisement .
From:
系统抽取对象
机构     
(1)
活动
出版物     
(1)
人物     
(1)
系统抽取主题     
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)  
(1)