To function correctly, superconducting quantum computers must be cooled to temperatures approaching absolute zero, roughly -273 degrees Celsius. At such ultra-low temperatures, electrons in the circuit move without resistance, enabling the formation and stability of quantum states. Despite the advancements in cryogenic technology, the cooling systems themselves ironically introduce unwanted noise and energy fluctuations. This noise interferes with quantum coherence and degrades the information stored within qubits, threatening the reliability and scalability of quantum devices.

Recognizing this paradox, researchers at Chalmers University of Technology in Sweden have pioneered a radically new approach to refrigeration at the quantum scale. Their breakthrough device is a minimalistic quantum refrigerator that intriguingly utilizes noise itself as the engine of cooling. This innovative concept turns the conventional challenge of noise into an opportunity, enabling exquisite control over minute heat and energy flows within quantum circuits that conventional refrigeration methods cannot achieve.

At the core of this pioneering quantum refrigerator is an engineered superconducting artificial molecule. Unlike molecules formed from atoms, this artificial molecule is constructed from nanoscale superconducting circuits that imitate molecular properties. This unique system is coupled to two microwave channels acting as thermal reservoirs with distinct temperatures, one hot and one cold. The researchers manipulate thermal energy transfer between these reservoirs by injecting controlled microwave noise through auxiliary ports, effectively using fluctuating signals to drive heat flow and refrigeration.

This process exploits an elusive and theorized phenomenon called Brownian refrigeration, where random thermal fluctuations—previously considered a nuisance—can induce and power a directed cooling effect. The Chalmers team’s work stands as the closest experimental realization of this concept. By finely tuning the noise spectrum in a narrow band of microwave frequencies, they successfully orchestrate the energy exchange pathways, transforming random fluctuations into a resource for thermal management in superconducting systems.

Remarkably, the refrigerator operates with extraordinary sensitivity, detecting heat currents as feeble as attowatts—a scale so minuscule that warming a water droplet by one degree Celsius using this heat flow would take longer than the age of the universe. The precision in measuring and manipulating thermal currents at this scale represents a significant technical milestone, pushing the limits of control over quantum thermodynamics and fostering new possibilities for managing heat in quantum hardware.

Beyond refrigeration, this quantum device exhibits multi-modal functionality. By adjusting reservoir temperatures and noise intensity, it can transition between acting as a refrigeration unit, a heat engine, or an amplifier of thermal transport. This versatility holds profound implications for future quantum computing architectures, where local heat management is vital as quantum processors grow larger and more intricate. Heat generated during qubit operations must be carefully controlled to prevent decoherence and maintain computational integrity.

The ability to direct and harness thermal energy at such a nanoscale addresses a critical bottleneck in scaling quantum technologies. Classical cooling methods, though effective at macroscopic levels, lack the finesse to manage energy fluxes within individual quantum circuits. The Chalmers quantum refrigerator exemplifies a new paradigm where cooling mechanisms are integrated directly into the quantum device and driven by the system’s intrinsic noise properties, enabling unprecedented robustness and stability.

This breakthrough also provides fundamental insights into quantum thermodynamics—a field exploring how energy and information intersect at quantum scales. Understanding how to exploit noise, dissipation, and fluctuations not simply as obstacles but as functional resources reshapes our approach to quantum machine design. Devices like this refrigerator open the door toward engineered quantum heat engines and refrigerators that can operate autonomously and efficiently within quantum computing environments.

Fabricated at Chalmers’ Nanofabrication Laboratory, the artificial molecule that underpins this quantum refrigerator comprises superconducting circuits engineered to carefully mimic two coupled qubits. The design ingeniously enables the controlled injection of noise, with the illegal flow of heat contingent upon this noise driving the transfer between thermal reservoirs. Through extensive experimental calibration, the researchers confirmed the delicate balance required to achieve refrigeration powered purely by stochastic fluctuations.

Simon Sundelin, the doctoral student leading this project, highlights how understanding energy transport pathways at the quantum level is paramount for future device design. Their findings enable the anticipation and regulation of heat flows, paving the way for quantum devices in which thermal energy is not a destructive byproduct but a parameter that can be predictably manipulated to enhance device performance.

The study’s co-author, Aamir Ali, underlines the importance of this work for practical quantum technology. By removing heat at scales unreachable by conventional refrigeration, this method could make quantum processors more reliable and scalable. It enhances prospects for building larger, more complex quantum computers that retain coherence for longer operational cycles, accelerating progress toward practical quantum advantage.

Simone Gasparinetti, associate professor and senior author, points out that this work is a major step in realizing Brownian refrigeration, a concept long thought to be only theoretical. By converting random thermal fluctuations into a cooling force, their experiment not only solves a pressing engineering problem but also deepens our fundamental understanding of thermodynamic processes in quantum systems.

As the quantum revolution unfolds, innovations like the noise-powered quantum refrigerator underscore the importance of marrying fundamental physics with engineering ingenuity. By harnessing the very noise that threatens quantum coherence, researchers have revealed a new pathway toward stable, scalable, and efficient quantum machines—ushering in an era where quantum heat management becomes a controllable asset rather than an insurmountable hurdle.

Subject of Research: Not applicable

Article Title: Quantum refrigeration powered by noise in a superconducting circuit

News Publication Date: 26-Jan-2026

Web References: https://doi.org/10.1038/s41467-025-67751-z

References: Sundelin, S., Aamir, M. A., Kulkarni, V. M., Castillo-Moreno, C., & Gasparinetti, S. (2026). Quantum refrigeration powered by noise in a superconducting circuit. Nature Communications.

Image Credits: Chalmers University of Technology / Simon Sundelin

Keywords: Quantum computing, Quantum information, Qubits

At the core of the metafilm’s functionality is its ability to passively cool surfaces by lowering temperatures by as much as 9.2°C under peak sunlight conditions. This impressive performance is complemented by its ability to reflect nearly 99% of solar radiation, which is crucial for reducing heat absorption in buildings. The potential implications for energy savings are profound, with estimates suggesting that the metafilm could lead to annual energy consumption reductions of up to 20% in some of the hottest urban areas.

Researchers employed a fabrication technique involving polylactic acid (PLA), a plant-derived bioplastic, to create the metafilm. This innovative low-temperature process not only maximizes the film’s reflective properties—reportedly reflecting 98.7% of sunlight—but also enhances its sustainability as an alternative to traditional materials. Conventional cooling technologies often rely on electrically powered systems that are detrimental to the environment, making the metafilm a compelling choice for environmentally conscious building practices.

The cooling mechanisms of the metafilm extend beyond just reflecting sunlight. It allows heat generated within the building to escape into outer space, a critical feature that maintains a cooler internal environment compared to the surrounding air. This function is vital in mitigating the need for air conditioning systems, which are known contributors to carbon emissions and environmental degradation. By providing a passive cooling solution that operates without electricity, the metafilm represents a leap forward in sustainable architecture.

Field trials conducted in both Australia and China demonstrated the metafilm’s stability under extreme conditions. Throughout the day, the film was observed to cause an average temperature drop of 4.9°C, with similar cooling performance observed at night. This robust performance persisted even after prolonged exposure to acidic conditions and intense ultraviolet light, two factors that typically compromise the integrity of biodegradable materials. After enduring 120 hours in a strong acid environment and the equivalent of eight months under outdoor UV stress, the metafilm still exhibited its cooling capabilities effectively.

The invention addresses a critical challenge faced by researchers in the field of materials engineering: the need for high-performance cooling options that are also eco-friendly. As urban areas continue to expand and heat up, the reliance on traditional cooling methods increases carbon footprints and energy use. The introduction of the bioplastic metafilm offers a powerful alternative; one that not only aligns with sustainable development goals but also lays the groundwork for large-scale applications across various sectors.

Furthermore, the bioplastic metafilm stands out as a long-lasting solution that retains its effectiveness over time. The researchers involved have indicated that the material not only delivers high solar reflectance and thermal emission but also degrades naturally, thus minimizing environmental impact over its lifecycle. This characteristic sets it apart from existing cooling materials that often rely on petrochemical-based solutions, raising concerns about their ecological footprint.

In potential real-world applications, this revolutionary metafilm could extend beyond cooling buildings—it can have implications in various domains, including agriculture, transport, electronics, and even in health care through applications like cooling wound dressings. Explore the opportunities for scalable manufacturing, whether for public structures or private residences, and the impact this could have on reducing reliance on fossil fuels.

Experts involved in the creation of the metafilm, including UniSA PhD candidate Yangzhe Hou and co-author Dr. Xianhu Liu, emphasize the importance of this material in countering the challenges posed by climate change and urban heat. Their collaborative work highlights the successful blend of sustainability with cutting-edge science and engineering principles, focusing on a future where eco-friendly technologies play a critical role in building resilience against global warming.

As cities like Lhasa in China anticipate energy consumption reductions by as much as 20.3% with the use of this metafilm, the urgency for sustainable solutions has never been greater. Urban planners and engineers are urged to consider the integration of this bioplastic metafilm into future projects, as the demands for energy efficiency and resilience grow increasingly urgent.

The biological and environmental overhaul promised by this innovative metafilm showcases the capacity of scientific research to address pressing global challenges. It reinforces the message that sustainability and high-performance engineering can coexist, paving the way for a future where buildings not only provide shelter but also serve as active participants in the fight against climate change. The research team looks to pursue advanced applications, potentially revolutionizing how our built environment interacts with the planet.

With positive implications for urban energy consumption and ecological health, the bioplastic metafilm stands as a testament to the power of interdisciplinary collaboration in driving innovation. The journey from lab-scale experiments to practical applications is just beginning, and the research community remains optimistic about leveraging this technology for broader impact.

The study detailing this significant advancement in passive cooling technology is published in the journal Cell Reports Physical Science, contributing vital knowledge to the fields of engineering and environmental science. As researchers and engineers continue to seek viable solutions to the challenges of climate change, the bioplastic metafilm represents a beacon of hope for a sustainable future.

Subject of Research: Bioplastic metafilm for passive cooling

Article Title: A structural bioplastic metafilm for durable passive radiative cooling

News Publication Date: 24-Jun-2025

Web References: DOI: 10.1016/j.xcrp.2025.102664

References: Published in Cell Reports Physical Science

Image Credits: University of South Australia

Keywords

• Materials engineering
• Biomaterials
• Sustainability
• Sustainable development
• Climate change mitigation