Qubits as Valves: Controlling Quantum Heat Engines
July 10, 2018 | Aalto UniversityEstimated reading time: 2 minutes
Researchers from Aalto University are designing nano-sized quantum heat engines to explore whether they may be able to outperform classical heat engines in terms of power and efficiency.
Image caption: With the valve, researchers can control the heat moving through the qubit. Image: Jorden Senior / Aalto University.
In their paper, published in Nature Physics, the group led by Professor Jukka Pekola presents a way to solve a problem in how quantum systems interact and exchange energy with their macroscopic surroundings, and within themselves. The group strives to treat quantum information and thermodynamics on the same footing in their research.
‘We have realised a miniature heat valve in a quantum system composed of an artificial atom, a superconducting qubit—the basic building block of both quantum computing and quantum heat engines,’ explains Professor Pekola.
While in quantum computers the qubit has to be decoupled from the noisy external world to sustain a fragile quantum state, in quantum heat engines, the system needs to be coupled to its dissipative surroundings, to heat baths.
A particularly puzzling problem is the process of thermalisation when connecting external heat sources or ‘thermal baths’ to a coherent quantum system or qubit. Ultimately, heat is exchanged between these systems through the emission of photons, one by one.
‘Using a qubit controlled by a magnetic field as a “valve”, we can either block or release the flow of photons carrying the heat through the qubit between two “heat baths” formed of metallic resistors,’ explains Dr. Alberto Ronzani, the lead author of the paper.
A quantum heat engine transforms heat into useful work or, in reverse, operates as a refrigerator.
‘Our work demonstrates how a heat valve can work in certain cases. We aim to understand, combining experimental and theoretical efforts, how quantum refrigerators and heat engines work, but have yet to come up with a general picture of the cross-over between non-dissipative and fully dissipative systems. That’s a challenge for the future,’ says Pekola.
In addition to Pekola and Ronzani, the team consists of doctoral students Bayan Karimi and Jorden Senior, Dr. Joonas Peltonen and additional collaborators Yu-Cheng Chang and Dr. ChiiDong Chen from the National Taiwan University and the Institute of Physics, Academia Sinica, in Taiwan, Republic of China, with experimental contributions to this work.
Jukka Pekola leads Quantum Technology Finland – Centre of Excellence funded by the Academy of Finland. The experimental research was carried out at the OtaNano national research infrastructure for micro, nano and quantum technologies in Finland.
Suggested Items
Real Time with... IPC APEX EXPO 2024: AI Implementation at Omron
04/18/2024 | Real Time with...IPC APEX EXPOEditor Nolan Johnson and Omron Product Manager Nick Fieldhouse discuss the company's focus on AI implementation to enhance customer experience and results. They address programming challenges and how AI can help customers achieve better outcomes with less experience. Omron's AI is compatible with existing systems, facilitating easy upgrades.
Cadence Unveils Palladium Z3 and Protium X3 Systems
04/18/2024 | Cadence Design SystemsThe Palladium Z3 and Protium X3 systems offer increased capacity, and scale from job sizes of 16 million gates up to 48 billion gates, so the largest SoCs can be tested as a whole rather than just partial models, ensuring proper functionality and performance.
Real Time with... IPC APEX EXPO 2024: MYCRONIC's Evolution and New Solutions
04/17/2024 | Real Time with...IPC APEX EXPOHenry Crandall interviews Kevin Clue, the vice president of global sales for MYCRONIC's High Flex division. They discuss the company's evolution, emphasizing its strong customer relationships and its role as a versatile, turnkey solution provider. Kevin unveils new solutions launched at IPC APEX EXPO, including an AI-integrated inspection system and the A40 pick-and-place platform. The conversation also touches on the increased use of AI and deep learning.
Australian Flow Batteries and The SCHMID Group Announce Groundbreaking Memorandum of Understanding
04/17/2024 | SCHMID GroupAustralian Flow Batteries Pty Ltd (AFB), a leader in innovative energy solutions and economical, safe, and reliable power storage, and SCHMID Energy Systems GmbH a company of the German SCHMID Group, a global technology leader with a rich history in delivering innovative solutions across multiple industries including Electronics, Renewables, and Energy Storage sectors, are thrilled to announce the signing of a Memorandum of Understanding (MoU)
Ansys Joins BAE Systems’ Mission Advantage Program to Advance Digital Engineering Across US Department of Defense
04/16/2024 | ANSYSAnsys announced it is working with BAE Systems, Inc., to accelerate the adoption of digital engineering and MBSE across the Department of Defense (DoD).