AI 中文总结
研究发现调谐至莫尔带半填充的魔角双层石墨烯可作为关联绝缘体莫尔测辐射热计，利用光子加热电子抑制关联能隙实现长波长辐射超灵敏探测
AI 中文摘要
入射到绝缘体上的光，通常不会在不引发导致瞬态结构转变的强超快激发的情况下将其转变为金属。这里我们表明，调谐至莫尔带半填充的魔角双层石墨烯是这一预期的显著例外。我们发现，能量与平带宽度相当的弱长波长光子束会选择性加热低热容量的电子子系统，从而抑制关联能隙。这产生的巨大电阻变化并非由持续的光载流子数量决定，而是由多体关联能隙对弱电子加热的极端敏感性决定。由此产生的光子驱动的绝缘体-金属转变产生了宽带低噪声光响应，电压响应率超过每纳瓦吸收功率毫伏。该机制与超导热电子响应是对偶的：辐射加热的电子抑制多体序，但相反，关联绝缘体熔化为金属，对几特斯拉的磁场具有鲁棒性，并呈现出尖锐的绝缘体-金属电阻对比。我们的结果确立了关联平带系统作为微弱长波长辐射超灵敏探测平台的潜力。
英文摘要
Light incident on an insulator is generally not expected to turn it into a metal without invoking intense ultrafast excitation that leads to transient structural transitions. Here we show that magic-angle twisted bilayer graphene tuned to half filling of the moiré band provides a notable exception to this expectation. We find that weak beam of long-wavelength photons, with energies comparable to the flat-band width, selectively heat the low-heat-capacity electronic subsystem, thereby suppressing the correlated gap. This produces a giant resistance change governed not by a persistent photocarrier population, but by the extreme sensitivity of a many-body correlated gap to weak electronic heating. The resulting photon-driven insulator-to-metal transition produces a broadband low-noise photoresponse with voltage responsivity exceeding millivolts per nW of absorbed power. The mechanism is dual to superconducting hot-electron response: radiation-heated electrons suppress a many-body order, but in reverse the correlated insulator melts into a metal, providing robustness to magnetic fields of several tesla and a sharp insulator-to-metal resistive contrast. Our results establish correlated flat-band systems as a platform for ultra-sensitive detection of faint long-wavelength radiation.
Comments37 pages and 20 figures (main text and SI together)
Journal refNature Communication 2025
DOI：10.1038/s41467-026-76389-4
