We report a novel nonequilibrium approach for direct laser writing diamond by melting amorphous polytetrafluoroethylene (PTFE:(C₂F₄) _n) in ambient conditions. The nanosecond laser pulses disintegrate PTFE, forming the undercooled molten carbon. This undercooled molten carbon regrows into diamond during the ultrafast melt quenching process, which lasts for ∼100 ns. HRTEM imaging, SAED, Raman, and EEL spectroscopy investigations confirm the first-order phase transformation of PTFE into single-crystalline <110> oriented diamond, which is associated with ultrafast unseeded crystallization. Our experimental findings open up a new pathway for the selective conversion of organic polymers into nano and microdiamonds and thin films with laser-writing.

我们报告了一种通过在环境条件下熔融非晶聚四氟乙烯（PTFE：（C ₂ F ₄） _n）直接激光写入钻石的新型非平衡方法。纳秒激光脉冲使PTFE分解，形成过冷的熔融碳。在超快熔体淬火过程中，这种过冷的熔融碳重新长成金刚石，持续约100 ns。HRTEM成像，SAED，拉曼和EEL光谱研究证实了PTFE进入单晶的一级相变<110>取向的金刚石，这与超快的非种子结晶有关。我们的实验发现为通过激光写入将有机聚合物选择性转化为纳米金刚石和微金刚石以及薄膜开辟了一条新途径。