Scientists at the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg, Germany, have been delving into the possibilities of using laser drives to manipulate quantum materials. In their recent groundbreaking experiment, the researchers discovered a significantly more efficient method of inducing a metastable, superconducting-like state using laser light. This discovery, published in Nature Physics, has the potential to revolutionize our understanding of photo-induced superconductivity.
In the realm of unconventional superconductors, researchers have observed enhanced electronic coherences and improved super-transport in non-equilibrium states. While these phenomena hold great promise, the complexity of the experiments has limited their systematic study and optimization. As a result, technological applications have remained out of reach. However, the Cavalleri group at MPSD has made significant strides in this field, thanks to their expertise in laser technology.
By fine-tuning the light source to a low frequency resonance of 10 THz, the researchers demonstrated that a significantly lower intensity of light pulses could induce the same effect at higher temperatures. This breakthrough is a game-changer as it allows for the efficient creation of a long-lived superconducting-like state in a fullerene-based material. In fact, the pulse intensity was reduced by a factor of 100 while still achieving the desired outcome. This photo-induced state was observed to persist at room temperature for 100 picoseconds and is predicted to retain its properties for at least 0.5 nanoseconds.
Lead author Edward Rowe, a Ph.D. student in the Cavalleri group, emphasizes the significance of the resonance frequency in understanding the underlying microscopic mechanism of photo-induced superconductivity. Currently, there is no widely accepted theoretical explanation for this effect in the specific material being studied. However, with the identification of the resonance frequency, theorists can now delve deeper into determining the key excitations at play. This knowledge opens up exciting possibilities for further research and potential applications.
Rowe believes that a light source with a higher repetition rate at the 10 THz frequency could prolong the lifespan of the metastable state. Ideally, if each new pulse can be delivered before the material returns to its non-superconducting equilibrium state, there is a possibility of sustaining the superconducting-like state indefinitely. This would be a significant milestone in the quest for practical applications of photo-induced superconductivity.
Andrea Cavalleri, Director of MPSD, commends the experiments conducted by the Cavalleri group, noting their demonstration of how advances in technology can make previously impractical phenomena applicable. Over two decades of dedicated exploration have culminated in these findings, marking a major convergence towards future technologies. The discovery not only sheds new light on photo-induced superconductivity but also paves the way for developing transformative technologies harnessing the properties of quantum materials.
With the utilization of tailored laser drives, scientists are unlocking the mysteries of non-equilibrium states and pushing the boundaries of what is possible in quantum materials. The recent breakthrough by the Cavalleri group at MPSD in creating a metastable, superconducting-like state at higher temperatures using reduced laser intensity has opened up new avenues for research and technological applications. By identifying the resonance frequency and understanding the microscopic mechanisms involved, we are one step closer to harnessing the full potential of photo-induced superconductivity. The future looks bright as advancements in laser technology continue to unravel the possibilities of quantum materials and pave the way for revolutionary technologies.