In a significant stride towards enhancing quantum transport in semiconductors, researchers from the University of Minnesota have unveiled a novel gating technique that could revolutionize the way we manipulate quantum devices. The study, led by Colin J. Riggert from the School of Physics and Astronomy, introduces an all-van der Waals (vdW) material-based gate, demonstrating its efficacy on InSb nanoribbons. This breakthrough, published in the journal *Materials for Quantum Technology* (translated to English as *Materials for Quantum Technology*), opens new avenues for clean quantum transport, with profound implications for the energy sector and beyond.
The research team, inspired by the improved transport quality observed in two-dimensional vdW materials when gated by other vdW materials, developed a method to apply this principle to non-vdW materials. By using a hexagonal boron nitride dielectric layer and a few-layer graphite gate electrode, they created an all-vdW gate stack. This innovative approach was successfully demonstrated on MOVPE-grown InSb nanoribbons, a novel variant of InSb nanowires with a flattened cross-section.
The results were striking. The all-vdW gated nanoribbon devices exhibited conductance features that were highly reproducible with minimal gate hysteresis. “We observed quantized conductance that persisted to lower magnetic fields and longer channel lengths than typical InSb nanowire devices reported to date,” Riggert explained. This level of performance is consistent with the reduced disorder expected from the all-vdW gating scheme, marking the first report of ballistic, few-modes quantum transport in a non-vdW material with an all-vdW gate.
One of the most intriguing findings was the highly anisotropic level splitting observed in an applied magnetic field, attributed to the ribbon cross-section. This discovery not only advances our understanding of quantum transport but also paves the way for potential applications in spintronics and topological superconductivity studies.
The implications of this research are far-reaching, particularly for the energy sector. Quantum transport plays a crucial role in the development of advanced energy technologies, including quantum computing and spintronic devices. The ability to achieve clean, reproducible quantum transport in non-vdW materials could accelerate the development of these technologies, leading to more efficient and sustainable energy solutions.
As the field of quantum technology continues to evolve, the work of Riggert and his team serves as a testament to the power of innovative materials science. By pushing the boundaries of what is possible with quantum transport, they are laying the groundwork for a future where quantum devices are more reliable, efficient, and scalable. This research not only advances our scientific understanding but also brings us one step closer to harnessing the full potential of quantum technologies for the benefit of society.